To solve this problem, we can use the formula for average velocity:
average velocity = (final velocity + initial velocity) / 2
We know that the average velocity of the jetliner while taxiing to a stop is -35 km/h. We also know that it takes 7.00 s for the plane to come to rest, so its final velocity is 0 km/h.
Using the formula above, we can solve for the initial velocity:
-35 = (0 + initial velocity) / 2
Multiplying both sides by 2, we get:
-70 = initial velocity
Therefore, the plane's initial velocity was -70 km/h.
Now we can use the formula for acceleration:
acceleration = (final velocity - initial velocity) / time
We know that the final velocity is 0 km/h, the initial velocity is -70 km/h, and the time it takes to come to rest is 7.00 s. Plugging these values into the formula, we get:
acceleration = (0 - (-70)) / 7
Simplifying, we get:
acceleration = 10 km/h/s
Therefore, the plane's acceleration was 10 km/h/s.
To know more about average velocity:
https://brainly.com/question/11265533
#SPJ11
On the cosmic calendar, which compresses the history of the universe into a single year, about when did life arise on Earth?
-in late January
-in mid-August
-in September
-in mid-December
-just a few hours before midnight on December 31
On the cosmic calendar, which compresses the history of the universe into a single year, life arose on Earth in September. This calendar, developed by Carl Sagan, represents the 13.8 billion years of the universe as a 12-month year. Each month is roughly 1.15 billion years, and each day is around 37.8 million years.
Life on Earth is believed to have begun around 3.5 to 4 billion years ago, during the Archean Eon. In the cosmic calendar, this period corresponds to September. The first life forms were simple, single-celled organisms, which eventually evolved into more complex multicellular organisms over billions of years.
It is important to note that the cosmic calendar is a visualization tool to help us understand the vastness of the universe and the relatively short time that life has existed on Earth compared to the age of the universe. The timeline demonstrates the immense scale of cosmic history and allows us to appreciate the rapid development of life on our planet within that context.
For more such questions on Cosmic calendar.
https://brainly.com/question/1054105#
#SPJ11
Three prominent spectral lines of wavelength \lambda are observed at 502nm, 587nm, and 667nm. What is the most likely composition of this sample?
The most likely composition of this sample is a mixture of ionized oxygen, hydrogen and iron.
What is meant by spectral lines of wavelength?Specific wavelengths of light that are emitted or absorbed by atoms or molecules are called as spectral lines. Each element has a unique set of spectral lines that are characteristic of that element.
The wavelengths given correspond to spectral lines of ionized oxygen, hydrogen, and iron, respectively. Therefore, most likely composition of the sample is mixture of these elements. It is important to note that other elements could also produce spectral lines at similar wavelengths, but given the prominence of these three lines, it is likely that these are the dominant elements in sample.
To know more about spectral lines, refer
https://brainly.com/question/28490374
#SPJ1
Spectral analysis of color flow Doppler most commonly performed by which technique ?
a. zero-crossing detectors
b. Fast Fourier transforms
c. autocorrelation
d. chirp-z transforms
The spectral analysis of color flow Doppler is most commonly performed by the Fast Fourier transform (FFT) technique.
The issue of quickly computing the Discrete Fourier Transform (DFT) of a series of numbers is resolved by the Cooley-Tukey Fast Fourier Transform technique.
A series of values are transformed from the time domain to the frequency domain using the DFT mathematical process. Several applications, including signal processing, data compression, and image processing, can benefit from this. The DFT can, however, be computationally expensive, particularly for lengthy sequences. With the Cooley-Tukey FFT algorithm, the number of operations needed to calculate the DFT is reduced from O(N²) to O(N log N), where N is the length of the sequence. This allows the DFT of big sequences to be computed in a reasonable period of time.
Learn more about Fast Fourier transform (FFT) technique here
https://brainly.com/question/30903096
#SPJ11
Suppose you ran 2km in 10min. With what speed did you run?
You ran at a speed of 12 km/h.
To calculate the speed at which you ran, we need to use the formula: speed = distance / time. In this case, the distance you ran is 2km and the time it took you is 10 minutes.
First, we need to convert the time to hours as the distance is given in kilometers per hour.
10 minutes = 10/60 hours = 0.1667 hours
Now we can substitute the values in the formula:
speed = distance / time = 2km / 0.1667 hours
This gives us a speed of approximately 12 kilometers per hour (km/h). Therefore, you ran at a speed of 12 km/h.
To learn more about speed, refer below:
https://brainly.com/question/28224010
#SPJ11
Two equal positive charges are near each other. If we increase the amount of charge on just one of them, then
If we increase the amount of charge on just one of the equal positive charges, then the distance between them will increase due to the electrostatic repulsion between them.
This is because the charge on the one that has been increased will become greater than the other, causing a stronger repulsive force between them.
Therefore, the charges will try to move away from each other in order to reduce the repulsive force.
The exact amount of distance increase will depend on the amount of charge added and the initial distance between them.
To know more about electrostatic repulsion here
https://brainly.com/question/132325
#SPJ11
A cannon ball is fired horizontally off a high cliff over a great distance. If air resistance can be ignored the path it follows is
A cannon ball is fired horizontally off a high cliff over a great distance. If air resistance can be ignored the path it follows is parabola.
Projectile motion is the movement of an item that has been launched into the air when there is little air resistance after the initial force that launches it and just gravity acting on the object. The trajectory of the item is referred to as the projectile's route.
An item or particle that is propelled into a gravitational field, such as from the surface of the Earth, and moves along a curved route only under the influence of gravity is said to be experiencing projectile motion. Most calculations make the assumption that the effects of air resistance are passive and insignificant in the specific instance of Earth projectile travel.
The trajectory of the projectile motion is always a parabola.
To know more about resistance :
https://brainly.com/question/4428352
#SPJ4.
Why are pith balls initially attracted to a charged rod and later repelled by the same rod after being touched, even though they have not touched any other object?
When a charged rod is brought near a neutral object like pith balls, it causes the electrons within the pith balls to move around. This creates a temporary separation of charges within the pith balls, with the end closest to the charged rod becoming oppositely charged to the other end. This attraction is due to the electrostatic force between opposite charges.
However, when the pith balls come into contact with the charged rod, some of the excess charge from the rod is transferred to the pith balls, causing them to become charged themselves. If the pith balls now have the same charge as the rod, they will be repelled due to the electrostatic force between like charges.
Therefore, the pith balls are initially attracted to the charged rod because of the temporary separation of charges within the pith balls. But once they come into contact with the charged rod and become charged themselves, they are repelled due to the like charges between the pith balls and the rod. It is important to note that the pith balls do not need to touch any other object to become charged, as the charged rod can transfer some of its charge to them upon contact.
To know more about pith balls click here:
https://brainly.com/question/31351061
#SPJ11
What will be the atomic radius of copper, if the distance between two adjacent copper atoms in metallic copper is 256 pm?
The atomic radius of copper is approximately 128 picometers (pm).
The atomic radius of an element is defined as half the distance between the nuclei of two identical adjacent atoms in a molecule. In the case of metallic copper, the copper atoms are arranged in a crystal lattice, and the distance between two adjacent copper atoms in the lattice is known as the interatomic distance or lattice parameter.
We are given that the distance between two adjacent copper atoms in metallic copper is 256 pm. Since this is the distance between the nuclei of two adjacent atoms, the sum of the atomic radii of the two copper atoms is equal to 256 pm.
Therefore, the atomic radius of copper can be calculated as follows:
Atomic radius of Cu = (interatomic distance between adjacent Cu atoms) / 2
Atomic radius of Cu = 256 pm / 2
Atomic radius of Cu = 128 pm
Hence, the atomic radius of copper is approximately 128 picometers (pm).
To learn more about picometers visit:
https://brainly.com/question/14272356
#SPJ11
a mass on a string of unknown length oscillates as a pendulum with a period of 5.5 s . part a what is the period if the mass is doubled?
A mass swings as a pendulum with a period of 5.5 seconds when it is
attached to a string of indeterminate length. The duration will remain 5.5
seconds.
According to the law of pendulum, the period (T) of a pendulum is given by:
T = 2π√(L/g)
where L is the length of the pendulum and
g is the acceleration due to gravity (approximately 9.81 [tex]m/s^2[/tex]).
Since the length of the pendulum is unknown, we cannot directly use this
formula to find the period.
However, we can use the fact that the period is constant for a given
pendulum, regardless of its mass.
So, if we double the mass of the pendulum, the period will remain the
same. Therefore, the period will still be 5.5 seconds.
for such more question on law of pendulum
https://brainly.com/question/21186335
#SPJ11
The approximate ratio of the Sun's diameter to the Earth's diameter, from the exercise in class, is about
a. 110 to 1
b. 1 to 110
c. 10 to 1
d. 1 to 10
You have a machine which can accelerate pucks on frictionless ice. Starting from rest, the puck travels a distance x in time t when force F is applied. If force 3F is applied, the distance the puck travels in time t is
1) x.
2) (3/2)x.
3) 3x.
4) (9/2)x.
5) 9x.
the distance traveled by an object is directly proportional to the applied force F and the time t, as long as the surface is frictionless. This can be expressed as d = (1/2)at^2, where a is the acceleration of the object.
When the force applied is increased to 3F, the acceleration of the puck will also increase by a factor of 3. This means that the distance traveled by the puck will increase by a factor of 3^2, or 9.
Therefore, the distance the puck travels in time t when force 3F is applied is 3x.
When a force F is applied on a puck on frictionless ice, it accelerates according to Newton's second law: F = ma, where m is the mass of the puck and a is its acceleration. Since the puck starts from rest, we can use the kinematic equation:
x = 1/2 * a * t^2
Since F = ma, a = F/m. Substituting this into the equation for x, we get:
x = 1/2 * (F/m) * t^2
Now, let's consider the case when the applied force is 3F. In this case, the acceleration will be:
a' = (3F)/m
Substituting this into the kinematic equation:
x' = 1/2 * (3F/m) * t^2
Now, we can divide the new equation by the original equation:
(x')/x = (1/2 * (3F/m) * t^2) / (1/2 * (F/m) * t^2)
Simplifying this expression, we get:
(x')/x = 3
Therefore, x' = 3x.
When force 3F is applied, the distance the puck travels in time t is 3x.
So the correct answer is option 3) 3x.
To know more about kinetic motion visit :
https://brainly.com/question/29775827
#SPJ11
The process below is an example of
.
23892U→23490Th+42He
.
a) beta emission
b) alpha emission
c) gamma emission
d) neutron emission
e) positron emission
The process shown is an example of alpha emission, as it involves the emission of an alpha particle (consisting of two protons and two neutrons) from the uranium nucleus to form the thorium nucleus.
The process you provided, 23892U → 23490Th + 42He, is an example of:
b) alpha emission
1. Identify the initial element and the products: The initial element is uranium-238 (23892U), and the products are thorium-234 (23490Th) and helium-4 (42He).
2. Compare the initial element and the products: The uranium-238 nucleus loses two protons and two neutrons, forming thorium-234 and a helium-4 nucleus.
3. Determine the type of radioactive decay: Since a helium-4 nucleus (also known as an alpha particle) is emitted, this process is an example of alpha emission.
To know more about alpha emission:
https://brainly.com/question/29835423
#SPJ11
monochromatic light is incident on a metal surface, and electrons are ejected. if the intensity of the light increases, what will happen to the maximum energy of the electrons? monochromatic light is incident on a metal surface, and electrons are ejected. if the intensity of the light increases, what will happen to the maximum energy of the electrons? the maximum energy will increase. changes in the maximum energy cannot be determined without additional information. the maximum energy will decrease. the maximum energy will remain the same.
When monochromatic light is incident on a metal surface, electrons may be ejected from the surface due to the photoelectric effect.
The energy of the ejected electrons is determined by the energy of the incident photons minus the energy required to overcome the work function of the metal (i.e., the minimum energy required to remove an electron from the metal).
The maximum energy of the ejected electrons is reached when the energy of the incident photons is equal to or greater than the work function of the metal.
If the energy of the incident photons is increased beyond this threshold, the maximum energy of the ejected electrons will not change.
However, if the intensity of the incident light is increased (i.e., the number of photons incident on the metal surface per unit time is increased), the number of ejected electrons per unit time will increase.
Since the energy of each ejected electron is determined by the energy of the incident photons, increasing the number of photons incident on the metal surface per unit time will increase the number of ejected electrons with higher energy (i.e., the maximum energy of the ejected electrons will increase).
This is because more electrons will be able to absorb photons with energies greater than the work function of the metal and gain higher energies as a result.
Therefore, the correct answer is: the maximum energy will increase.
To know more about photoelectric effect :
https://brainly.com/question/26465043
#SPJ11
if a person is prescribed glasses that have a power of 2.75 diopters where the glasses sit 2.0 cm from their eye, what is their eyes near point? the normal near point is 25 cm. (2 pts) 64.6 cm (b) if a person is prescribed glasses that have a power of -1.30 diopters where the glasses sit 2.0 cm from their eye, what is their far point? the normal far point is infinity. (2 pts) 78.9 cm g
a.64.6 cm is their eyes near point and b.78.9 cm is their far point in normal far point is infinity in prescribed glasses.
Farsightedness, also referred to as hyperopia, is an eye refractive mistake in which light entering the eye is concentrated behind the retina rather than directly on it, impairing vision of close objects.
For the first question, we can use the formula 1/f = 1/do + 1/di, where f is the focal length, do is the object distance, and di is the image distance. We know that the glasses have a power of 2.75 diopters, so the focal length is
f = 1/2.75 m = 0.364 m. The object distance is do = 2.0 cm = 0.02 m. Solving for di, we get:
1/0.364 = 1/0.02 + 1/di
di = 64.6 cm
So the person's near point is 64.6 cm, which is farther than the normal near point of 25 cm.
For the second question, we can again use the same formula, but this time we know that the power of the glasses is -1.30 diopters, which means the focal length is f = -1/1.30 m = -0.769 m (the negative sign indicates a diverging lens). The object distance is the same as before, do = 2.0 cm = 0.02 m. Solving for di, we get:
-1/0.769 = 1/0.02 + 1/di
di = 78.9 cm
So the person's far point is 78.9 cm, which is closer than the normal far point of infinity.
Learn more about hyperopia here
https://brainly.com/question/31413647
#SPJ11
29) Cognitive Psychology: How does this approach explain psychopathologies? What is the main focus of cognitive therapy? What role self-efficacy plays here?
Cognitive psychology explains psychopathologies as resulting from faulty thinking patterns and negative beliefs that can be modified through cognitive therapy.
The main focus of cognitive therapy is to identify and change these maladaptive thoughts and beliefs, leading to improved mental health.
Self-efficacy, or one's belief in their ability to accomplish a task or achieve a goal, plays a significant role in cognitive therapy as it can impact motivation, behavior, and overall mental well-being.
Cognitive psychology provides a framework for understanding how thoughts, beliefs, and mental processes can influence behavior and mental health. This approach views psychopathologies as resulting from faulty thinking patterns and negative beliefs that can be modified through cognitive therapy.
For example, individuals with depression may have negative thoughts and beliefs about themselves, their environment, and their future that contribute to their symptoms. Cognitive therapy aims to identify and change these maladaptive thoughts and beliefs, replacing them with more positive and realistic ones, leading to improved mental health.
The main focus of cognitive therapy is to identify and modify maladaptive thoughts and beliefs, leading to improved mental health. This therapy may involve techniques such as cognitive restructuring, where the therapist helps the patient identify and replace negative thoughts and beliefs with more positive and realistic ones. It may also involve behavioral experiments, where the patient is encouraged to test their beliefs in a safe and controlled environment, leading to increased self-efficacy and confidence.
Self-efficacy, or one's belief in their ability to accomplish a task or achieve a goal, plays a significant role in cognitive therapy. It can impact motivation, behavior, and overall mental well-being. In cognitive therapy, therapists aim to increase their patient's self-efficacy by helping them develop realistic and achievable goals, providing positive feedback, and encouraging them to take small steps towards their goals. As patients experience success and build their self-efficacy, they may be more likely to continue engaging in positive behaviors and maintain their mental health.
To know more on cognitive therapy
https://brainly.com/question/30039388
#SPJ4
the angular speed of a rotor in a centrifuge increases from 478 to 1320 rad/s in a time of 4.79 s. (a) obtain the angle through which the rotor turns. (b) what is the magnitude of the angular acceleration?
Given the angular speed of a rotor in a centrifuge increases from 478 to 1320 rad/s in a time of 4.79 s.
To find the magnitude of the angular acceleration, we can use the following equation:
angular acceleration (α) = (final angular speed - initial angular speed) / time
In your question, the initial angular speed is 478 rad/s, the final angular speed is 1320 rad/s, and the time taken is 4.79 s. Plugging these values into the equation:
α = (1320 rad/s - 478 rad/s) / 4.79 s
α = (842 rad/s) / 4.79 s
α ≈ 175.78 rad/s²
The magnitude of the angular acceleration is approximately 175.78 rad/s².
To know more about magnitude of the angular acceleration:
https://brainly.com/question/30238737
#SPJ11
1, 6-diaminohexane is used to make nylon. what is the empirical formula of this compound if it is 62.1% C, 13.8% H, and 24.1% N?
The empirical formula of 1,6-diaminohexane is C3H8N.
What is the empirical formula of 1,6-diaminohexane with a composition of 62.1% C, 13.8% H, and 24.1% N?
To find the empirical formula, we need to determine the simplest whole-number ratio of atoms in the compound.
First, we can assume a 100-gram sample of the compound. This means that 62.1 grams of the sample are carbon, 13.8 grams are hydrogen, and 24.1 grams are nitrogen.
Next, we need to convert the masses of each element to moles using their respective atomic masses:
Moles of carbon = 62.1 g / 12.01 g/mol = 5.17 mol
Moles of hydrogen = 13.8 g / 1.01 g/mol = 13.7 mol
Moles of nitrogen = 24.1 g / 14.01 g/mol = 1.72 mol
Now, we divide each mole value by the smallest mole value to obtain the simplest whole-number ratio of atoms:
Carbon: 5.17 mol / 1.72 mol = 3
Hydrogen: 13.7 mol / 1.72 mol = 8
Nitrogen: 1.72 mol / 1.72 mol = 1
Therefore, the empirical formula of 1,6-diaminohexane is C3H8N.
To learn more about empirical formula, visit: https://brainly.com/question/14576568
#SPJ1
Two skaters collide an embrace, in a completely inelastic collision. That is, they stick together after impact. The origin is placed at the point of collision. Alfred, whose mass is 83 kg, is originally moving east with speed 6.2 km/h. Barbara, whose mass is 55 kg, is originally moving north with speed 7.8 km/h.What is the velocity v of the couple after impact? Hint: You must find vx, vy and the angle theta.
The velocity of the couple after impact is v = 4.11 km/h at an angle of 51.8° north of east.
First, convert Alfred's and Barbara's velocities to m/s:
Alfred's velocity = 6.2 km/h = 1.72 m/s eastBarbara's velocity = 7.8 km/h = 2.17 m/s northSince momentum is conserved in an inelastic collision, we can write:
(m_Alfred)(v_Alfred) + (m_Barbara)(v_Barbara) = (m_Alfred + m_Barbara)vPlugging in the values:
(83 kg)(1.72 m/s) + (55 kg)(2.17 m/s) = (83 kg + 55 kg) vSolving for v:
v = 1.87 m/sNow we need to find the x- and y-components of v. Using trigonometry:
vx = v cos(theta)vy = v sin(theta)We can find theta by using the fact that the tangent of the angle between the velocity vector and the x-axis is vy/vx:
tan(theta) = vy/vxPlugging in the values:
tan(theta) = (2.17 m/s) / (1.72 m/s)theta = 51.8°Therefore:
vx = v cos(theta) = 1.19 m/svy = v sin(theta) = 1.65 m/sFinally, we convert back to km/h:
vx = 4.28 km/h eastvy = 5.94 km/h northSo the velocity of the couple after impact is 4.11 km/h at an angle of 51.8° north of east.
To learn more about conservation of momentum, here
https://brainly.com/question/3920210
#SPJ4
Two hoops or rings (I = MR2) are centered, lying on a turntable. The smaller ring has radius = 0.050 m; the larger has radius = 0.10 m. Both have a mass of 3.0 kg. What is the total moment of inertia as the turntable spins? Ignore the mass of the turntable.
A total moment of inertia of 0.0375 kg·m² as the turntable spins.
What is the total moment of inertia as the turntable spins?The total moment of inertia of the two hoops or rings on the turntable can be calculated using the formula I = MR². The moment of inertia of each hoop can be calculated separately and then added together to find the total moment of inertia.
For the smaller hoop, the moment of inertia would be I = (3.0 kg)(0.050 m)² = 0.0075 kg·m².
For the larger hoop, the moment of inertia would be I = (3.0 kg)(0.10 m)² = 0.030 kg·m².
Adding these two values together gives a total moment of inertia of 0.0375 kg·m² as the turntable spins.
It's important to note that the mass of the turntable is ignored in this calculation, as instructed in the question. Also, the term "moment" in this context refers to moment of inertia, which is a measure of an object's resistance to rotational motion.
Learn more about moment of inertia.
brainly.com/question/15246709
#SPJ11
In which system is heat usually transferred from the cooler part to the warmer part?
a. A stove as it heats up water
b. A refrigerator that is running
c. An electric fan that is running
d. None of the above, because it is impossible to transfer heat in this manner
The system in which heat is usually transferred from the cooler part to the warmer part is a refrigerator that is running.
By the application of external electricity supply in a refrigerator, the heat transfer occurs from the low temperature region to the region of higher temperature.
In a refrigerator, the cooler part is inside the refrigerator and the warmer part is the surrounding environment.
To learn more about heat transfer, click:
https://brainly.com/question/16084179
#SPJ4
at a certain temperature and pressure, chlorine molecules have an average velocity of 324 m/s. what is the average velocity of sulfur dioxide molecules under the same conditions?
Under the same conditions, the average velocity of sulfur dioxide molecules is 340 m/s
Graham's Law of Effusion:
Under the same temperature and pressure conditions, the average velocity of different gas molecules can be compared using the equation derived from Graham's Law of Effusion:
v1 / v2 = √(M2 / M1)
where v1 is the average velocity of chlorine molecules, v2 is the average velocity of sulfur dioxide molecules, M1 is the molar mass of chlorine, and M2 is the molar mass of sulfur dioxide.
The molar mass of chlorine (Cl2) is approximately 70.9 g/mol, and the molar mass of sulfur dioxide (SO2) is approximately 64.1 g/mol.
Given that average velocity of chlorine molecules (v1) is 324 m/s, The average velocity of sulfur dioxide molecules (v2):
v2 = v1 * √(M1 / M2) = 324 m/s * √(70.9 g/mol / 64.1 g/mol) ≈ 340 m/s
Under the same temperature and pressure conditions, the average velocity of sulfur dioxide molecules is approximately 340 m/s.
To know more about Graham's Law visit:
https://brainly.com/question/31488584
#SPJ11
Under the same conditions, the average velocity of sulfur dioxide molecules is 340 m/s
Graham's Law of Effusion:
Under the same temperature and pressure conditions, the average velocity of different gas molecules can be compared using the equation derived from Graham's Law of Effusion:
v₁ / v₂ = √(M2 / M1)
where v₁ is the average velocity of chlorine molecules,v₂ is the average velocity of sulfur dioxide molecules, M1 is the molar mass of chlorine, and M₂ is the molar mass of sulfur dioxide.
The molar mass of chlorine (Cl₂) is approximately 70.9 g/mol, and the molar mass of sulfur dioxide (SO₂) is approximately 64.1 g/mol.
Given that average velocity of chlorine molecules (v₁) is 324 m/s, The average velocity of sulfur dioxide molecules (v₂):
v₂ = v₁ * √(M1 / M2) = 324 m/s * √(70.9 g/mol / 64.1 g/mol) ≈ 340 m/s
Under the same temperature and pressure conditions, the average velocity of sulfur dioxide molecules is approximately 340 m/s.
To know more about Graham's Law visit:
brainly.com/question/31488584
#SPJ4
Which artifact results in improper side-by-side positioning reflectors ?
a. mulipath
b. comet tail
c. refraction
d. reverberation
The artifact that results in improper side-by-side positioning reflectors is c. refraction. The refractive index of the surface causes the incident ray to deviate from its intended path when it enters the refracting surface.
The angle formed by the refracted beam and the surface's perpendicular is known as the angle of refraction.
Normal refers to the surface's perpendicular.
The angle between the refracted light and the Normal is hence the angle of refraction.
The refractive index of a material gives clues about its capacity to bend light.It establishes how much light is bent or refracted along its route.It has no dimensions at all.When light waves cross the line separating two materials with different densities, like air and glass, their speed changes. They alter their direction as a result, which is referred to as refraction.
the rate of change of light as it passes through one medium and then enters another. Refraction results from this. The difference in media affects how light travels through the atmosphere and into water.
Learn more about refraction here
https://brainly.com/question/2660868
#SPJ11
a horizontal water jet from a nozzle of constant exit cross section impinges normally on a stationary ver- tical flat plate. a certain force f is required to hold the plate against the water stream. if the water velocity is doubled, will the necessary holding force also be doubled? explain.
A horizontal water jet from a nozzle of constant exit cross-section impinges normally on a stationary vertical flat plate.A certain force f is required to hold the plate against the water stream. If the water velocity is doubled, the necessary holding force will not be doubled; instead, it will be quadrupled.
1. When the water jet hits the plate, its velocity changes due to the change in momentum, which results in a force acting on the plate.
2. The force acting on the plate can be determined using the equation F = Δ(mv)/Δt, where F is the force, m is the mass of the water, v is the velocity, and Δt is the change in time.
3. Since the exit cross-section of the nozzle is constant, the mass flow rate of the water (mass per unit time) remains the same, even when the velocity is doubled.
4. If the velocity of the water is doubled, the momentum change (Δ(mv)) will also be doubled because the mass remains constant.
5. Now, let's substitute the doubled velocity in the force equation: F = Δ(2mv)/Δt.
6. The equation now becomes F = 2(Δ(mv)/Δt), which means that the force is twice the original force.
7. Since we've already doubled the momentum change and now doubled the force, the overall change in the necessary holding force will be 2 * 2 = 4 times the original force.
So, when the water velocity is doubled, the necessary holding force to keep the plate stationary will be quadrupled, not doubled.
Learn more about velocity here:
https://brainly.com/question/80295
#SPJ11
Calculate the sound pressure level in dB relative to 20 μPa (20 micropascals) produced by an acoustic pressure of 40,000 μPa.
A. 3.3 dB
B. 66 dB
C. 72 dB
D. 2000 dB
To calculate the sound pressure level in dB relative to 20 μPa produced by an acoustic pressure of 40,000 μPa, you can use the following formula:
Sound Pressure Level (dB) = 20 × log10(P1 / P0)
where P1 is the acoustic pressure (40,000 μPa) and P0 is the reference pressure (20 μPa).
Step 1: Calculate the ratio of P1 to P0:
Ratio = P1 / P0 = 40,000 μPa / 20 μPa = 2000
Step 2: Calculate the logarithm base 10 of the ratio:
log10(2000) ≈ 3.3
Step 3: Multiply the logarithm result by 20:
Sound Pressure Level (dB) = 20 × 3.3 = 66 dB
So, the sound pressure level relative to 20 μPa produced by an acoustic pressure of 40,000 μPa is 66 dB. The correct answer is B. 66 dB.
To know more about Sound Pressure Level :
https://brainly.com/question/17579180
#SPJ11
What is the magnitude and direction of the electric field due to a point charge of 20μC at a distance of 1 meter away from it?
Knowing that k=8.99×109N⋅m2 / C2
Answer:
aqnweser of magnitude of the x)2 of the arrow of the manginutre filed
Explanation:
A motor boat's speed in still water is 2.0 m/s. The driver wants to go directly across a river with a current speed of 1.5 m/s.At what angle upstream should the boat be steered?
The motorboat should be steered at an angle of approximately 41.19° upstream to go directly across the river.
To determine the angle upstream at which the motorboat should be steered, we need to consider the boat's speed in still water (2.0 m/s) and the river's current speed (1.5 m/s).
At what angle upstream should the boat be steered?
Step 1: Create a right triangle with the boat's speed as the hypotenuse and the river's current speed as one of the legs.
Step 2: Use the Pythagorean theorem to find the remaining leg (opposite side). In this case, it would represent the component of the boat's speed that is perpendicular to the river current.
[tex]opposite^2 + adjacent^2 = hypotenuse^2[/tex]
[tex]opposite^2 + (1.5 m/s)^2 = (2.0 m/s)^2[/tex]
Step 3: Solve for the opposite side (let's call it O):
[tex]O^2 = (2.0 m/s)^2 - (1.5 m/s)^2[/tex]
[tex]O^2 = 4 - 2.25[/tex]
[tex]O = √1.75 ≈ 1.32 m/s[/tex]
Step 4: Use the tangent function to find the angle θ.
tan(θ) = opposite/adjacent
tan(θ) = 1.32 m/s / 1.5 m/s
Step 5: Calculate the angle θ.
θ = arctan(1.32 m/s / 1.5 m/s) ≈ 41.19°
So, the motorboat should be steered at an angle of approximately 41.19° upstream to go directly across the river.
To know more about Pythagorean theorem:
https://brainly.com/question/14930619
#SPJ11
A massless 1.5 m rod connects 2 equal point masses, one at each end of the rod. If the kinetic energy is 36 J when rotating this system at 3 rad/s about an axis perpendicular to the rod through one end of the rod, what is the value of the moment of inertia of the system?
To find the moment of inertia of the system, we can use the formula for the moment of inertia of a rod rotating about an axis perpendicular to it:
I = (1/12) * m * L^2
Where I is the moment of inertia, m is the mass of the rod, and L is the length of the rod.
Since the rod is massless, we only need to find the moment of inertia of the two point masses at the ends of the rod. Since they are equal, we can divide the total moment of inertia by 2 to get the moment of inertia of one of them.
To find the mass of each point mass, we can use the fact that the kinetic energy of the system is equal to the rotational kinetic energy of the two masses:
KE = (1/2) * I * w^2
Where KE is the kinetic energy, I is the moment of inertia, and w is the angular velocity.
Substituting the given values, we get:
36 J = (1/2) * I * (3 rad/s)^2
Solving for I, we get:
I = (2 * KE) / w^2
= (2 * 36 J) / (3 rad/s)^2
= 8 kg * m^2
Since we have two equal point masses, the moment of inertia of each one is:
I/2 = 4 kg * m^2
Therefore, the value of the moment of inertia of the system is 4 kg * m^2.
To know more about moment of inertia:
https://brainly.com/question/30051108
#SPJ11
A 5-g lead bullet traveling in 20°C air at 300 m/s strikes a flat steel plate and stops.What is the final temperature of the lead bullet? (Assume the bullet retains all heat.)
The melting point of lead is 327°C. The specific heat of lead is 0.128 J/g⋅°C.
The heat of fusion of lead is:
a. 227°C
b. 260°C
c. 293°C
d. 327°C
The heat of fusion of lead is (a) 227°C.To solve this problem, we need to use the principle of conservation of energy, which states that the total energy in a closed system remains constant.
Option D is Correct answer. The ultimate temperature is well below the lead's (327°C) melting point.
To find the final temperature of the lead bullet, we need to use the equation for heat transfer
Q = mCΔT
where Q is the heat transferred, m is the mass of the bullet, C is the specific heat of lead, and ΔT is the change in temperature.
First, we need to find the initial temperature of the bullet. We are given that the air temperature is 20°C, but we don't know the initial temperature of the bullet. However, we can assume that the bullet is at the same temperature as the air before it strikes the steel plate. Therefore, the initial temperature of the bullet is also 20°C.
Next, we need to find the heat transferred when the bullet strikes the steel plate. We can assume that all of the kinetic energy of the bullet is converted into heat when it stops. Therefore:
Q = 0.5mv²
where m is the mass of the bullet and v is its velocity. Plugging in the values, we get:
Q = 0.5×(5 g)×(300 m/s)² = 2.25 J
Finally, we can use the equation for heat transfer to find the final temperature of the bullet:
ΔT = Q / (mC)
ΔT = 2.25 J / (5 g x 0.128 J/g °C) = 3.52°C
Therefore, the final temperature of the lead bullet is 20°C - 3.52°C = 16.48°C.
Note that this final temperature is well below the melting point of lead (327°C), so the bullet will remain solid. The heat of fusion of lead is not needed to solve this problem.
Learn more about melting point here
https://brainly.com/question/29578567
#SPJ11
why are icebergs often surrounded by fog? 1. the evaporation from an iceberg condenses into droplets (fog). 2. the air is dryer near an iceberg. 3. an iceberg attracts vapor from the surrounding air. 4. the chilled air in the vicinity of an iceberg results in condensation of water vapor in the air (fog).
Icebergs are surrounded by fog as :4)The chilled air in the vicinity of iceberg results in condensation of water vapor in air (fog).
Why are icebergs surrounded by fog?Icebergs are much colder than the surrounding air and water, which creates temperature difference between water and air near the iceberg. This temperature difference can cause air to cool and become saturated with water vapor, which can then condense into fog. This is similar to how fog forms over a lake or river on cool morning.
As the air cools near the iceberg, the water vapor in air condenses into tiny water droplets that create fog. This fog can be quite dense, making it difficult for ships and boats to navigate around the iceberg.
To know more about iceberg, refer
https://brainly.com/question/1244519
#SPJ1
Light incident on a 0.15 mm wide slit forms a diffraction pattern on a screen 6 m away. If the first minimum of the diffraction pattern is 2 cm from the central peak, what is the wavelength of the incident light? a. 350 nm b. 420 nm c. 500 nm d. 550 nm
To determine the wavelength of the incident light, we will use the single-slit diffraction formula:
sin(θ) = (m * λ) / a
where θ is the angle of the minimum, m is the order of the minimum (in this case, m = 1 for the first minimum), λ is the wavelength, and a is the slit width.
First, we need to find θ. Since the screen is 6 m away and the first minimum is 2 cm (0.02 m) from the central peak, we can use the tangent function:
tan(θ) = (0.02 m) / (6 m)
θ = arctan((0.02 m) / (6 m))
Now, we can plug the values we have into the single-slit diffraction formula:
sin(θ) = (1 * λ) / (0.15 mm)
λ = a * sin(θ)
We need to convert the slit width to meters:
a = 0.15 mm = 0.00015 m
Now we can find the wavelength:
λ = 0.00015 m * sin(arctan((0.02 m) / (6 m)))
λ ≈ 4.2 x 10^-7 m = 420 nm
So, the wavelength of the incident light is approximately 420 nm (option b).
To know more about single-slit diffraction :
https://brainly.com/question/14099055
#SPJ11