Plant trees on places where forests have been chopped down to restore damaged ecosystems. Encourage individuals to live in a way that is environmentally friendly. Create parks to conserve the rainforests and animals. Companies that operate in environmentally friendly methods should be supported.
A 1.0-g string that is 0.64 m long is fixed at both ends and is under tension. This string produces a 100-Hz tone when it vibrates in the third harmonic. The speed of sound in air is 344 m/s. The tension in the string is closest to
The tension in the given string of 1.0 g and length of 0.64 m is closest to 2.84 N
Tension in the string
The tension in the string at nth harmonic is calculated as follows;
[tex]f_n = \frac{n}{2l} \sqrt{\frac{T}{\mu} }[/tex]
where;
n th harmonic = 3L is length of the string = 0.64 mμ is mass per unit length = (1 x 10⁻³ kg)/(0.64 m) = 0.00156 kg/mf is frequency = 100 HzT is tension in the string = ?[tex]f_n = \frac{n}{2l} \sqrt{\frac{T}{\mu} }\\\\\frac{f_n(2l)}{n} = \sqrt{\frac{T}{\mu} }\\\\\frac{f_n^2(4l^2)}{n^2} = \frac{T}{\mu} \\\\T = \mu (\frac{f_n^2(4l^2)}{n^2})\\\\T = 0.00156(\frac{100^2 \times 4\times 0.64^2}{3^2} )\\\\T = 2.84 \ N[/tex]
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suggest why it is better to use light gates and a computer than to use a stopwatch and a ruler to measure the speed of a toy car
Human response times are eliminated from time measurement using light gates. if the stopwatch is damaged, the data logger terminates it.
What is speed?Speed is defined as the rate of change of the distance or the height attained. it is a time-based quantity. it is denoted by u for the initial speed while u for the final speed. its si unit is m/sec.
To measure the speed of a toy automobile, it is preferable to utilize light gates and a computer as opposed to a stopwatch and a ruler.
Because Light gates eliminate the effects of human reaction delays for measuring time. is damaged,
The stopwatch is stopped by the data logger. With no reaction time, the uncertainty is substantially reduced.
The average speed may be determined by measuring the distance between the two light gates.
Hence, it is better to use light gates and a computer than to use a stopwatch and a ruler to measure the speed of a toy car.
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what is contact and non-contact force ?
define frictional force ,normal reaction force, tension force as applied through string,force exerted by spring, force exerted by during collision, gravitational force , electrostatic force ,magnetic force.
Explanation:
Hello !
Contact force:-A contact force is any force that requires contact to occur. examples Applied force,
Normal force,
Frictional force,
Tension force,
Air resistance force,
Spring force.
Non-contact force:-is a force which acts on an object without coming physically in contact with it. types of non-contact forces are gravitational force, magnetic force, electrostatic and nuclear force.
frictional force:-is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other.
Normal reaction force:-A force acting perpendicular to two surfaces in contact with each other.
The tension force is defined as the force that is transmitted through a rope, string or wire when pulled by forces acting from opposite sides.
The force exerted by a spring on objects attached to its ends is proportional to the spring's change in length away from its equilibrium length and is always directed towards its equilibrium position. F = -kx. The proportional constant k is called the spring constant.
During the collision, each body exerts a force on the other. This force is called an impulsive force.
The gravitational force :-is a force that attracts any two objects with mass. We call the gravitational force attractive because it always tries to pull masses together, it never pushes them apart.
The electrostatic force is also known as the Coulomb force or Coulomb interaction. It's the attractive or repulsive force between two electrically charged objects.
magnetic force, attraction or repulsion that arises between electrically charged particles because of their motion.
What cloud extending to the gravitational limits of the solar system would comets come from?.
The Oort cloud extends to the gravitational limits of the solar system would comets come from.
What is oort cloud?It is a hypothetical idea of a cloud of mostly frozen planetesimals that would orbit the Sun at distances between 2,000 and 200,000 AU.
The Oort cloud reaches the solar system's outer gravitational boundaries, where comets originate.
Hence cloud extending to the gravitational limits of the solar system will be oorto cloud.
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Which action can humans take to reduce wave erosion?
build drainage systems
build houses near coastlines
build breakwaters in the ocean
reduce vegetation along coastlines
The action that humans can take to reduce wave erosion is to build breakwaters in the ocean.
What is erosion?The term erosion has to do with the washing away of top soil either by water or by wind. The control of erosion is a very important soil conservation effort.
Hence, the action that humans can take to reduce wave erosion is to build breakwaters in the ocean.
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Answer: (C) build breakwaters in the ocean
Explanation: Got it on edge
With a burst of speed, Kevin swims one 25.0-m stretch in 9.22 s. What is Kevin's average speed over those 25 m
If Kevin swims one 25.0-m stretch in 9.22 seconds, his average speed is approximately 2.71m/s.
What is Kevin's average speed over those 25 m?Speed is expressed as distance over time.
Speed = Distance / time
Given the data in the question
Distance = 25.0mTime elapsed = 9.22sAverage speed = ?Average speed = 25.0m / 9.22s
Average speed = 2.71m/s
If Kevin swims one 25.0-m stretch in 9.22 seconds, his average speed is approximately 2.71m/s.
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Transparent or translucent materials
are used to make
A stop signs
B suitcases
C color filters
D toothbrushes
Answer:
C
Explanation:
you need to be able to see through a colour filter, which means youd need transparent or translucent
Transparent materials passes light and they reflect also. The color filters are made by transparent or translucent materials. Thus option c is correct.
What is transparency?The ability of a material to pass light through it is called transparency. Some transparent materials can reflect the light. For example mirror, glasses etc. The materials which passes light but are not transparent is called translucent materials.
The material which does not pass light inside is called opaque. Wood, plastics etc. are opaque materials. Transparent covers, glasses make their inside visible.
Colour filters are made by transparent or translucent materials. They are used to filter or choose a particular colour from a group of reflected lights.
Color filters are used in spectrometers and other optical devices. They filter the incoming wavelengths to select the desired one. Hence, option c is correct.
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3. State Newton's first and second laws of equation. A. A body of mass 2kg move vertically upwards has its velocity increased uniformly from 15m/s to 45m/s in 5s. neglecting air resistance, the upward vertical force acting on the body. [g=10ms 2] B. The velocity ratio and efficiency of pulley are 8 and 85% respectively. How much effort is required to lift a load of 120kg with this system [g=10m/s²]
Answer:
See below.
Explanation:
Newton's First Law
A body at rest persists in its state of rest, and a body in motion remains in constant motion along a straight line unless acted upon by an external force.
Newton's Second Law
A body's acceleration is directly proportional to the force exerted on it and is in the same direction as the force. F=mA (Force = Mass x Acceleration)
==============================================
A. A body of mass 2kg move vertically upwards has its velocity increased uniformly from 15m/s to 45m/s in 5s. neglecting air resistance, the upward vertical force acting on the body. [g=10ms 2] B. The velocity ratio and efficiency of pulley are 8 and 85% respectively. How much effort is required to lift a load of 120kg with this system [g=10m/s²]
Force = Mass x Acceleration
Acceleration is (45m/s - 15 m/s)/5 sec) or 6 m/sec^2
Force = 2kg*(6 m/sec^2)
Force = 12 kg*m/s^2 1 kg*m/s^2 is the SI unit for force, and is named 1 Newton(N), after . . . Newton.
Force = 12N
B. I'm not sure how to interpret "The velocity ratio and efficiency of pulley are 8 and 85% respectively." I'll assume "effort" is the energy required.
I'll calculate the energy required in a perfect system, and then we'll consider the efficiency issues.
By lifting an object with mass off the Earth's surface (height = 0 meters) we impart a potential energy, PE, to the object. This energy is stored in the object until it is allowed to move back closer to Earth. This potential energy is given by the equation:
PE = mgh
where PE is potential energy in Joules, m is mass in kg, g is the acceleration due to Earth's gravity (9.8 m/sec^2, but we'll use 10 m/sec^2 as stated in the problem), and h is the vertical distance moved, in meters.
PE = (120kg)(10 m/sec^2)(h). We aren't given a height, h. Let's express the answer in terms of 1 meter: How much potential energy is put into the 120kg load to raise it 1 meter?
PE = (120kg)(10 m/sec^2)(1 m)
PE = 1200 kg*m^2/sec^2 or 1200 kg*m/sec^2 per meter
The unit kg*m/sec^2 is 1 Joule
PE = 1200 Joules/meter
1200 Joules are required to raise 120kg 1 meter. This is increased due to the less-tha-100% efficiency of 85%.
At 85% efficiency, the energy required would be 1200J/0.85 = 1412 J to raise 120kg 1 meter, with 85% efficiency, I don't6 know how to handle the velocity ratio number.
1. When building a house using bricks a damp course is laid just above the brick foundation. Explain why the damp course is necessary
Answer:
Damp Proofing:
Explanation:
The presence of damp proofing is very necessary to maintain the health of a structure. DPC plays an important role in all types of buildings and it should be necessary to know about the importance, requirements, and properties of DPC. In many of the buildings all over the world, the rising damp may be due to a damaged damp-proof course, or sometimes, there may be not any damp proof course in a building.
I turn a glass upside down, trap the air in it by putting it in water, and then i take the glass down to 10 metres/33 feet. The air space would
The air space would be half the size it was at the surface.
What is airspace?It should be noted that airspace means the portion of the atmosphere controlled by a country that's above its territory.
Based on the information given, the The air space would be half the size it was at the surface.
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two point charges of magnitude 4.0 μc and -4.0 μc are situated along the x-axis at x1 = 2.0 m and x2 = -2.0 m, respectively. what is the electric potential at the origin of the xy-coordinate system?
The electric potential at the origin of the xy coordinate system is negative infinity
What is the electric field due to the 4.0 μC charge?The electric field due to the 4.0 μC charge is E = kq/r² where
k = electric constant = 9.0 × 10 Nm²/C², q = 4.0 μC = 4.0 × 10 C and r = distance of charge from origin = x₁ - 0 = 2.0 m - 0 m = 2.0 mWhat is the electric field due to the -4.0 μC charge?The electric field due to the -4.0 μC charge is E = kq'/r² where
k = electric constant = 9.0 × 10 Nm²/C², q' = -4.0 μC = -4.0 × 10 C and r = distance of charge from origin = 0 - x₂ = 0 - (-2.0 m) = 0 m + 2.0 m = 2.0 mSince both electric fields are equal in magnitude and directed along the negative x-axis, the net electric field at the origin is
E" = E + E'
= -2E
= -2kq/r²
What is the electric potential at the origin?So, the electric potential at the origin is V = -∫₂⁰E".dr
= -∫₂⁰-2kq/r².dr
Since E and dr = dx are parallel and r = x, we have
= -∫₂⁰-2kqdxcos0/x²
= 2kq∫₂⁰dx/x²
= 2kq[-1/x]₂⁰
= -2kq[1/x]₂⁰
= -2kq[1/0 - 1/2]
= -2kq[∞ - 1/2]
= -2kq[∞]
= -∞
So, the electric potential at the origin of the xy coordinate system is negative infinity
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A doctor has a patient blow on one side of a U-shaped tube that is partially filled with water and has a ball floating on the other side, as shown in the image below. If the ball rises with a force of 150 N, what pressure did the patient apply to his side of the tube?
A.
0.15 Pa
b.
150Pa
c.
100,000 Pa
D.
150,000 Pa
The patient apply pressure to his side of the tube is 15 x 10⁴ N/m². The correct option is D.
What is pressure?The pressure is the amount of force applied per unit area. It is represented as
Pressure p = Force/Area
Given is a doctor has a patient blow on one side of a U-shaped tube that is partially filled with water and has a ball floating on the other side. The ball rises with a force of 150 N. The cross section are of the tube is 0.001 m³
The pressure applied is
p = 150 /0.001
p = 15 x 10⁴ N/m²
Hence, the patient apply pressure to his side of the tube is 15 x 10⁴ N/m².
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Draw a ray diagram for a diverging lens that has a focal length of -10 cm when an object is placed 30 cm from the lens's surface. Calculate the position of the image and list the characteristics of the image.
Explanation:
Hello, nice to meet you.
this answer will help for you
The tip of a fan blade is 0.61 m from the center of the fan. the fan turns at a constant speed and completes 2 rotations every 1.0 s. what is the centripetal acceleration of the tip of the fan blade?
The centripetal acceleration of the tip of the fan blade is 96.23 m/s²
What is centripetal acceleration?The acceleration developed when a body is moving in circular way, directed towards the center of the circular path.
The tip of a fan blade is 0.61 m from the center of the fan. the fan turns at a constant speed and completes 2 rotations every 1.0 s
ac = ω²r
where ω = angular speed = 2πN/60, N = Rotation per minute
From the question, N = 2 x 60/1 = 120 RPM
So, the angular speed will be
ω = 2π x 120 /60
ω = 12.56 rad/s
Then, the centripetal acceleration is
ac = (12.56)² x 0.61 m
ac = 96.23 m/s²
Thus, centripetal acceleration of the tip of the fan blade is 96.23 m/s²
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8. in a hall experiment, a current of 25 a is passed through a long foil of ag, which is 0.1 mm thick and 3mm long. calculate the hall voltage produces across the width by a flux of 1.4 w/m2. if the conduction of ag is 6.8x10mho/m. estimate the mobility and hall coefficient.
The mobility and hall coefficient willl be 57.7 ×10⁻⁴ and 29.41 ×10⁻⁶ v.
What is electric current?Electric current is defined as the ratio of the charge flow in a given time interval. It is denoted by I. It has the unit is ampere.
Given data;
Electric current,I= 25 A
Thickness = 0.1 mm
Length = 3 mm
Flux = 1.4 w/m²
The charge density is found as;
[tex]\rm \rho =- \frac{1}{R_H} \\\\ \rho = 0.119 \times 10^{11} C/m^3[/tex]
The value of the hall voltage is;
[tex]\rm V_H = BVd \\\\ V_H = B \frac{I}{\rho dt} d \\\\ V_H = \frac{BI}{\rho t } \\\\ V_H = \frac{0.14 \times 25 }{0.119 \times 10^{11} \times 0.1 \times 10^{-3}} \\\\ V_H = \frac{3.5 }{0.119 \times 10^7} \\\\ V_H = 29.41 \times 10^{-6} \ v[/tex]
The mobility of electrons is;
[tex]\rm \mu_e = \frac{\rho}{n_e}\\\\ \mu_e = \frac{6.848 \times 10^7}{13.5 \times 10^{-30}\times 1.607 \times 10^{-19}} \\\\ \mu_e = 57.7 \times 10^{-4}[/tex]
Hence the mobility and hall coefficient willl be 57.7 ×10⁻⁴ and 29.41 ×10⁻⁶ v.
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When you attract every object in the universe with a force that is proportional to the mass of the objects and to the distance between them, you are obeying which law?
When you attract every object in the universe with a force that is proportional to the mass of the objects and to the distance between them, we are obeying Newton's law of universal gravitation.
Newton's law of universal gravitationNewton's law of universal gravitation states that the force of attraction between two masses in the universe is directly proportional to the product of the masses and inversely proportional to the the square of the distance between them.
The mathematical interpretation of the above law is
F ∝Mm/r²Removing the proportionality sign,
F = GMm/r².Where:
F = Force of attractionG = Gravitational constantM = Bigger massm = Smaller mass r = Distance between the masses.
From the above, When you attract every object in the universe with a force that is proportional to the mass of the objects and to the distance between them, we are obeying Newton's law of universal gravitation.
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what type of bulb is unaffected
Nothing happens to the brightness of the light bulbs in the parallel circuit if the power supply is capable of supplying the additional current.
the question is confusing
Alpha particles have highest mass.
Alpha particles are most ionising.
Gamma particles are the most penetrating.
Beta particles are negatively charged.
Gamma particles have the highest speed.
Comparing the three types of ionizing radiation-alpha particles have the greatest mass. Alpha particles have approx 4 times the mass of a proton or neutron and 8,000 times the mass of a beta particle. Ionising power of alpha particle is very high due to double positive charge, large mass as compared to a beta particle. Alpha particles can cause multiple ionisations within a very small distance. Beta radiation is more penetrating than alpha radiation. beta radiation can pass through the skin, but it is absorbed by a few cm of tissue of the body or a few mm of aluminum. Gamma radiation is the most penetrating of the three radiations. Alpha particles are positively charged, while beta particles are negatively charged, and gamma radiation is electrically neutral. Gamma rays are similar to visible light but they have higher energy. Gamma rays are emitted along with alpha or beta particles during radioactive decay.learn more about gamma rays here:
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You push a 50.0 kg box across a floor at a constant speed of 2.0m/s. If the coefficient of friction between the two surfaces is 0.20, then how much force are you exerting on the box? If you stop pushing, then how far will the box slide before coming to rest? Start by drawing a FBD.
(a) The force applied on the box is 98 N.
(b) When you stop pushing, the displacement of the box before coming to rest is 1.02 m.
Force exerted on the box
The force exerted on the box is calculated from Newton's second law of motion.
F - Ff = ma
where;
a is acceleration of the boxF is applied forceFf is frictional forceat constant speed, a = 0
F - Ff = 0
F = Ff
Ff = μmg
Ff = 0.2 x 50 x 9.8
Ff = 98 N
When you stop pushing, applied force = 0F - Ff = ma
-Ff = ma
a = -Ff/m
a = -98/50
a = - 1.96 m/s²
Displacement of the boxv² = u² + 2as
when the box stops, v = 0
0 = u² + 2as
0 = (2)² + 2(-1.96)s
0 = 4 - 3.92s
3.92s = 4
s = 4/3.92
s = 1.02 m
When you stop pushing, the displacement of the box before coming to rest is 1.02 m.
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which factors can change the size of the shadow of an opaque object
a)the color of the object b)the material the object is made from
c)how far the object is from the light source d)the size of the screen
Answer:
it have two answers a and c
Explanation:
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Answer: c)how far the object is from the light source
d)the size of the screen
The size of the shadow depends on the distance of the source of light and on the angle at which the light rays fall on the object. If the source of light is closer to the object, a larger shadow is formed than when the source of light is far from the object.
The angle at which a light strikes an object affects the size and shape of its shadow. Shadows are longer when the light source is at a low angle (side on) and shorter when the light source is at a higher angle (overhead).
The position of the light source can change the size and shape of a shadow. A good example would be, when we are outside on a sunny day, we can see how our shadows change throughout the day. The Sun's position in the sky affects the length of the shadow.
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One of the properties of alkali metals is that they don’t react with water.
Beryllium (Be) is the only alkaline earth metal that does not react with water.
What are alkali metals and their properties?
Alkali is a substance that produces hydroxide ions in aqueous solution.
PHYSICAL PROPERTIES OF ALKALIS:
Alkalis have a BITTER taste & have a SOAPY touch.Alkalis turn RED litmus paper BLUE.Alkalis have a pH value > 7.Alkalis are CAUSTIC.Alkalis CONDUCT ELECTRICITY due to the presence of MOBILE IONS in solution.CHEMICAL PROPERTIES OF ALKALI METAL
Alkalis react with Acids to form salt and water. This reaction is called neutralisation reaction.Alkalis react with ammonium salts to form salt, water and ammonia gas. .Alkalis react with solution of metal salt to form another metal salt and hydroxide.Beryllium (Be) is the only alkaline earth metal that does not react with water.
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What is the concentration of H+ ions at a pH = 8?
mol/L
What is the concentration of OH– ions at a pH = 8?
mol/L
Taking into account the definition of pH and pOH, the concentration of H⁺ ions at pH=8 is 1×10⁻⁸ M and the concentration of OH⁻ ions at pH=8 is 1×10⁻⁶ M.
Definition of pHpH is a measure of acidity or alkalinity that indicates the amount of hydrogen ions present in a solution or substance.
The pH is defined as the negative base 10 logarithm of the activity of hydrogen ions, that is, the concentration of hydrogen ions or H₃O⁺:
pH= - log [H⁺]= - log [H₃O⁺]
Definition of pOHSimilarly, pOH is a measure of hydroxyl ions in a solution and is expressed as the logarithm of the concentration of OH⁻ ions, with the sign changed:
pOH= - log [OH⁻]
Relationship between pH and pOHThe following relationship can be established between pH and pOH:
pOH + pH= 14
Concentration of H⁺ ionsIn this case, pH=8. Replacing in the definition of pH:
8= - log [H⁺]
Solving:
[H⁺]= 10⁻⁸= 1×10⁻⁸ M
Finally, the concentration of H⁺ ions at pH=8 is 1×10⁻⁸ M.
Concentration of OH⁻ ionsBeing pH= 8, pOH is calculated as:
pOH + 8= 14
pOH= 14 - 8
pOH= 6
Replacing in the definition of pOH the concentration of OH⁻ ions is obtained:
- log [OH⁻]= 6
Solving
[OH⁻]= 10⁻⁶= 1×10⁻⁶ M
Finally, the concentration of OH⁻ ions at pH=8 is 1×10⁻⁶ M.
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Which of the following would increase the amount of electricity generated by a wind turbine
Higher wind speeds would increase the amount of electricity generated by a wind turbine.
What is a power plant?A power plant is an industrial structure that generates electricity. The majority of power plants are linked to the electrical grid.
Stronger winds produce greater power because they enable the blades to revolve more quickly. Greater mechanical and electrical power from the generator result from faster spinning.
Hence, higher wind speeds would increase the amount of electricity generated by a wind turbine.
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Sonam and Wangchuk are taking part in a long jump event during their school's annual sports day. Sonam ran a few distances before taking the jump while Wangchuk jumped without running. Who will jump furthest? Justify your answer.
Answer:
Sonam will jump further than wangchuck
Which of the following consists of photovoltaic cells?
1. Solar panels
2. Rube Goldberg device
3. Solar oven
4. Electric generator
3. Magnetite is
a) Natural magnet
(b)Artificial magnet
(c) Not a magnet
[tex] \huge \bold \red {Aɴswᴇʀ}[/tex]
Magnetite is a Natural magnet
The event in the life of a star that begins its expansion into a giant is Group of answer choices almost all the hydrogen in its core that was hot enough for fusion has been turned into helium as much as 90% of the star explodes violently the core reaches a temperature of ten million degrees the star's internal structure reaches equilibrium for the first time in its life
The event in the life of a star that begins its expansion into a giant is that almost all the hydrogen in its core that was hot enough for fusion has been turned into helium.
What is a fusion reaction?A fusion reaction is defined as the type of nuclear reaction whereby two or more atomic nuclei combine to form a heavier nucleus.
The stars are being transformed into giants through fusion reaction.
A higher amount of hydrogen is found in the core of the star which is being use up in the fusion reaction to form helium.
When the hydrogen in the centre of a star runs out, the star begins to use hydrogen further out from its core. This causes the outer layers of the star to expand and cool.
Therefore, the event in the life of a star that begins its expansion into a giant is that almost all the hydrogen in its core that was hot enough for fusion has been turned into helium.
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If a ball is thrown into the air with a velocity of 45 ft/s, its height in feet after t seconds is given by y=45t-15t2. Find the instantaneous velocity when t=4
Given that a ball is thrown into the air and its height in feet after t seconds is given by y = 45t - 15t², the instantaneous velocity when t=4 is -75ft/s.
What is the instantaneous velocity when t=4?Given that;
Initial velocity = 45ft/sHeight in feet after t seconds is given by y = 45t - 15t² Instantaneous velocity = ?First, we determine the derivative of y = 45t - 15t²
y' = (1)45 - (2)15t
y' = 45 - 30t
We substitute in t = 4
y' = 45 - 30t
y' = 45 - 30(4)
y' = 45 - 120
y' = -75ft/s
Given that a ball is thrown into the air and its height in feet after t seconds is given by y = 45t - 15t², the instantaneous velocity when t=4 is -75ft/s.
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a ball is thrown upward from the ground with an initial velocity of 50m/s. what is the total time spent by the ball in the air (g=10m/s2)
Answer:
[tex]\fbox {5 seconds}[/tex]
Explanation:
The formula which is used here :
[tex]\fbox {v = u + at}[/tex]
[tex]\longrightarrow \textsf {v : final velocity}[/tex]
[tex]\longrightarrow \textsf {u : initial velocity}[/tex]
[tex]\longrightarrow \textsf {a : acceleration}[/tex]
[tex]\longrightarrow \textsf {t : time taken}[/tex]
Solving :
v = u + at
0 = 50 + (-10)t
10t = 50
t = 5 seconds
a compact car is about 1289 kg and its engine has the ability to generate 183831 W. if all that power is applied from a stand still and no energy is dissipated, how fast will the car be moving after 7 seconds.
The speed of the car moving after 7 seconds will be 31.5 m/sec.
What is velocity?The change of distance with respect to time is defined as speed. Speed is a scalar quantity. It is a time-based component. Its unit is m/sec.
The given data in the problem is
m is the mass of the car = 1289 Kg.
u is the initial velocity = 0 m/sec
a is the acceleration in m/sec²
v is the velocity after 7 seconds =?
The power developed is;
P =FV
F=ma
P=maV
183831=1289 kg × a × V
a = 142.61 / V
From Newton's second equation of motion;
V=u+at
V=0+at
V=(142.61/V)t
V²=142.61 × 7
V=31.5 m/sec
Hence, the speed of the car moving after 7 seconds will be 31.5 m/sec.
To learn more about the velocity, refer to the link: https://brainly.com/question/862972.
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