r
[tex]- \frac{mR^2 }{I } \ v[/tex]Answer:
a) w = - [tex]\frac{m r }{I} v[/tex] , b) W = - ½ m_woman R² (1 + m_woman R / I²) v²
Explanation:
a) To solve this exercise, let's use the conservation of angular momentum.
We define a system formed by the table and the woman, therefore the torques are internal and the moment is conserved
initial instant. Before starting to move the woman
L₀ = 0
final instant. After starting to move
L_f = I w + m v r
the moment is preserved
L₀ = L_f
0 = Iw + m v r
w = - [tex]\frac{m r }{I} v[/tex] (1)
the direction of the angular velocity is opposite to the direction of the linear velocity, that is, counterclockwise
b) for this part we use the relationship between work and kinetic energy
W = ΔK
in this case the initial speed is zero and the final speed of the table, using the relationship between linear and angular variables
v = w r
we substitute
W = 0 - ½ I_total w²
I_total = I + m_{woman} R²
W = - ½ (I + m_woman R²) ( [tex]\frac{m_{woman} R}{I} \ v[/tex]) ²
W = - ½ (m_woman² R² + m_woman³ R³ / I²) v²
W = - ½ m_woman R² (1 + m_woman R / I²) v²
Two rams run toward each other. One ram has a mass of 49 kg and runs west
with a speed of 7 m/s, while the other has a mass of 52 kg and runs east with
a speed of 9 m/s. What will the momentum of the system made up of the two
rams be after they collide? Assume the total momentum of the system is
conserved
A. 811 kg-m/s west
B. 811 kg-m/s east
C. 125 kg-m/s west
O D. 125 kg-m/s east
S
Answer: (d)
Explanation:
Given
Mass of the first ram [tex]m_1=49\ kg[/tex]
The velocity of this ram is [tex]v_1=-7\ m/s[/tex]
Mass of the second ram [tex]m_2=52\ kg[/tex]
The velocity of this ram [tex]v_2=9\ m/s[/tex]
They combined after the collision
Conserving the momentum
[tex]\Rightarrow m_1v_1+m_2v_2=(m_1+m_2)v\\\Rightarrow 49\times (-7)+52\times (9)=(52+49)v\\\Rightarrow v=\dfrac{125}{101}\ m/s \quad[\text{east}][/tex]
Momentum after the collision will be
[tex]\Rightarrow 101\times \dfrac{125}{101}=125\ kg-m/s\ \text{East}[/tex]
Therefore, option (d) is correct
a baseball with a mass of 0.8 kg is moving at asperd of 45.0 m/s . what is the baseballs kinetic energy
SOMEONE HELP PLEASE!!
Answer:
0.5*0.8*45^2. =810J
Explanation:
KE=1/2 mv^2
what causes waves to slow down: change in wave’s wavelength or change in its frequency and y?
Answer:
Although the wave slows down, its frequency remains the same, due to the fact that its wavelength is shorter. When waves travel from one medium to another the frequency never changes.
When does the Northern Hemisphere receive more of the Sun’s thermal energy than the Southern Hemisphere?
a. When the North Pole is tilted away from the Sun.
b. When the North Pole is tilted toward the Sun.
c. The North Pole never receives more of the Sun’s thermal energy.
d. When the Earth is closer to the Sun during its orbit.
Answer:
B
Explanation:
The Southern Hemisphere reflects a tremendous amount of radiation during the December solstice.
Northern Hemisphere receives more of the Sun’s thermal energy than the Southern Hemisphere. in the situation when the North Pole is tilted toward the Sun.
What is Sun’s thermal energy?One of the most important renewable energy sources is solar thermal energy. Solar thermal systems transform solar energy into heat.
Which may be used directly or converted into electricity for use in any application that can be served by conventional power.
The Northern Hemisphere is located well above the Equator, whilst the Southern Hemisphere is located below it.
The hemispheres include distinct quantities of land, ocean, and sea, as well as varied populations and climate patterns.
When the North Pole is tilted toward the Sun the Northern Hemisphere receives more of the Sun’s thermal energy than the Southern Hemisphere.
Hence option b is correct.
To learn more about the Sun’s thermal energy refer to the link;
https://brainly.com/question/24267059
How much force is needed to accelerate a 7.1 kg skier at 4 m/s/s?
Answer: 28.4
Explanation:
F=MA
F=(7.1)(4)
F= 28.4 N
Technician A says that high-intensity discharge (HID) headlights are brighter and have a blue tint. Technician B says that one defective turn signal bulb can cause the turn signal on the affected side to stop blinking (flashing). Who is right?
a) technician A
b) technician B
c) both technicians A and B
d) neither technician A nor B
Answer:
The right option is;
d) Both technicians A and B
Explanation:
High-intensity discharge (HID) headlights is an electrical gas-discharge light that gives a very bright light when an arc is formed between the tungsten electrodes that have a transparent or translucent housing
The light is ideal for night driving due to its brightness and appear to have a bluish tint at night although the light produced by HID headlight is actually more similar to Sunlight around noon
A turn signal bulb is a flashing light indicator that shows that a vehicle is about to turn or change lanes
An issue with the wiring, a broken connection at the bulb socket or a burnt bulb can result in a condition of "no turn signal" in which the turn signal stops flashing or blinking. Therefore both technicians A and B are correct.
What are the northern lights?
Answer:
The northern lights, one of several astronomical phenomena called polar lights (aurora Polaris), are shafts or curtains of colored light visible on occasion in the night sky.
Explanation:
Help! (science class)
Answer:
opposite charges.
1. two Styrofoam.
2. pieces of glitter.
3. balloon moves away from glass rod
like charges
1. two sweaters cling
2. balloons stick to wall
3. stream of water bends
HELP HELP HELP I WILL MARK AS BRAINLIEST
Answer:
sun, jupiter, earth, moon
Explanation:
how big they are
Answer:
sun, jupiter, earth, moon. sun
Explanation:
The sun would have the biggest gravity because it is the massiest.
Based on the mass of each planet, this is the correct answer.
Match each sound feature to its description
amplitude
the density of the medium's particles
at the compressions of the wave
compression
the part of a wave where the particles
of the medium are farther apart
wavelength
the distance between compressions
or rarefactions
rarefaction
the part of a wave where the particles
of the medium are closer together
Intro
Done
tivity
be here to search
GOS
Answer:
1. Amplitude.
2. Rarefaction.
3. Wavelength.
4. Compression.
Explanation:
Sound are mechanical waves that are highly dependent on matter for their propagation and transmission. Some of the properties of sound waves as it travels through a medium such as solid, liquid and gas includes the following;
1. Amplitude: the density of the medium's particles at the compressions of the waves.
2. Rarefaction: the part of a wave where the particles of the medium are farther apart. This ultimately implies that, it is part of a longitudinal wave in which the particles that make up the matter for the movement of the wave are separated by a greater distance.
3. Wavelength: the distance between compressions or rarefactions i.e the distance between two successive compressions or refractions.
4. Compression: the part of a wave where the particles of the medium are closer together. This ultimately implies that, it is part of a longitudinal wave in which the particles that make up the matter for the movement of the wave are closer together.
Answer:
here is the answers .......
Which of the following describes a seamount?
A. ocean floor at the edge of a continental margin
B. underwater mountain range
C. sediment piled at the base of the continental slope
D. underwater volcano that is more than 1 km high
Answer:
B. underwater mountain range
Answer:
an underwater mountain range
What and where is the asteroid belt?
Please ANSWER THIS
Answer:
The asteroid belt is a region of our solar system, between the orbits of Mars and Jupiter, in which many small bodies orbit our sun.
Explanation:
Hope this helps!
Answer:
The asteroid belt (sometimes referred to as the main asteroid belt) orbits between Mars and Jupiter. It consists of asteroids and minor planets forming a disk around the sun. It also serves as a sort of dividing line between the inner rocky planets and outer gas giants.
Explanation:
Hope this helps! :)
Consider a projectile. Which of the following describes y-motion? Check all that apply.
1. The y motion is a vertical motion.
2. The y motion is a horizontal motion
3. A projectile covers different distances per second in the direction.
4. A projectile covers equal distance per second in this direction
Answer:
1. True - gravity affects the y motion
2. False - x-coordinates affect the horizontal motion
3. y because gravity affects motion in the y-direction
4. x generally no external forces act in the x direction and hence no acceleration in the x direction
PLEASE HELP ASAPPPP!!!!!
Katrina replaced the batteries in her camera with rechargeable ones. Later as she was recharging the batteries, Katrina told her mother “I am creating energy so that I can use these batteries again!” What was Katrina actually doing?
removing energy
destroying energy
transforming energy
repairing energy
A7
A car of mass 15ookg, tr
mass 15ookg, travelling at a
Steedy spead, has
kinetic energy of 2004
о a
What is
the speed of the car?
What is it
Answer:
v = 1.63 m/s
Explanation:
Given that,
The mass of a car, m = 1500 kg
The kinetic energy of a car, K = 2004 m/s
We need to find the speed of a car. The formula for the speed of a car is given by :
[tex]K=\dfrac{1}{2}mv^2\\\\v=\sqrt{\dfrac{2K}{m}} \\\\v=\sqrt{\dfrac{2\times 2004}{1500}} \\\\v=1.63\ m/s[/tex]
So, the speed of the car is equal to 1.63 m/s.
Answer:taking my points !
Explanation:
What is the time it takes an object that moves at 25 m/min to travel 505 meters?
Answer:
25 meters = 1 minute
505 meters = ? minutes
Therefore, 505/25
Therefore, 101/5
Therefore, 2.2 minutes
It moves 505 meters in 2.2min
Can you help me please?
Answer:
a/ oscillating charges
Two in-phase sources of waves are separated by a distance of 3.50 m. These sources produce identical waves that have a wavelength of 5.96 m. On the line between them, there are two places at which the same type of interference occurs (a) Is it constructive or destructive interference, and (b) where are the places located?
Answer:
(a) It is a destructive interference
(b) The places at which destructive interference occur on the line between the two in-phase sources, are 1.07798 m before and after the two sources
Explanation:
(a) The given parameters are;
The distance between the two in-phase sources, d = 3.50 m
The type of waves produced by the two sources = identical waves
The wavelength of the waves produced by the two sources, λ = 5.96 m
For constructive interference, we have;
d·sin(θ) = m·λ
Where, m = 0, 1, -1, 2, -2, ...
For destructive interference, we have;
[tex]d \cdot sin(\theta) = \left(m + \dfrac{1}{2} \right) \cdot \lambda[/tex]
d·sin(θ) = Δl =
Where, m = 0, 1, -1, 2, -2, ...
Therefore, given that λ > d, for constructive interference
sin(θ) = m·λ/d > 1 for m > 0 which is invalid as the maximum value for sin(θ) = 1
Therefore, the possible interference is destructive interference
(b) For destructive interference, when m = 0, we have;
[tex]3.5 \times sin(\theta) = \left(0 + \dfrac{1}{2} \right) \times 5.96[/tex]
∴ sin(θ) = (5.96/2)/3.5
θ = arcsin((5.96/2)/3.5)
By trigonometry, we have;
tan(θ) = (d/2)/l
Where
l = The location along the line
∴ l = (d/2)/(tan(θ))
By substitution, we have;
l = (3.5/2)/(tan(arcsin((5.96/2)/3.5))) = 1.07798
Therefore, the two locations along the line where there is a destructive are 1.07798 m along the line before and after the two in-phase sources.
The displacement current density between the plates of a parallel-plate capacitor is uniform and has a magnitude of 19.9 A/m2 as the capacitor is being charged. What is dE/dt, the rate at which the electric field strength is changing between the plates
Answer:
[tex]\dfrac{dE}{dt} \approx 2.261 \overline {36} \times 10^{12} \ V/ms[/tex]
Explanation:
The parameters given in the question are;
The magnitude of the displacement current density between the plates of a parallel-plate capacitor, J = 19.9 A/m²
We have;
[tex]i_d = \epsilon _0 \times \dfrac{d \Phi_E}{dt} =\epsilon _0 \times A \times \dfrac{d E}{dt}[/tex]
Therefore;
[tex]\therefore \dfrac{dE}{dt} =\dfrac{i_d}{\epsilon _0 \cdot A} =\dfrac{J}{\epsilon_0} = \dfrac{19.9}{8.8 \times 10^{-12}} \approx 2.261 \overline {36} \times 10^{12}[/tex]
Therefore;
[tex]\therefore \dfrac{dE}{dt} \approx 2.261 \overline {36} \times 10^{12} \ V/ms[/tex]
When does the edge of the water advance farther inland- when the ocean's floor is a gradual slope or steep slope?
Answer:
The correct answer is when the slope is steep.
Explanation:
The advancement of water inland is dependent on the rate at which water wears off the continental shelf and the coastal plain. The higher the amount of rainfall, and the harshness of the dry spells, the faster the rate of erosion that occurs at the coastal plain.
As the erosion increases, the coastal plain becomes steeper. The steeper the plain, the water flowing erodes the coastal plain at a faster rate. Hence the water advances farther inland faster than where the slope is gentle or gradual.
Cheers
On a sunny day, as the distance from your hand to the ground increases, the shadow of your hand on the ground become fuzzier because:
Answer:
the Sun is a circle in the sky and that creates a penumbra
Explanation:
A penumbra is basically a lighter and hazy outer part of the shadow. It is the partially shaded portion of the outer region of a shadow that is cast by an opaque object.
In the context, as the distance from the hand to the surface of the ground increases on a sunny day, the shadow of the hand that falls on the ground becomes fuzzier because the sun is an opaque object in the sky and it creates a penumbra which makes the shadow of the hand on the ground fuzzier as the distance is increased.
Two identical balls are thrown from the top of a cliff, each with the same speed. One is thrown straight up, the other straight down. How do the kinetic energies and speeds of the balls compare as they strike the ground?
A) The ball that is thrown straight up will have more kinetic energy but less speed than the ball that is thrown straight down.
B) The ball that is thrown straight up will have more kinetic energy and more speed than the ball that is thrown straight down.
Both balls will have the same kinetic energy and speed.
C) The ball that is thrown straight up will have more kinetic energy but less speed than the ball that is thrown straight down.
D) The ball that is thrown straight down will have more kinetic energy and more speed than the ball that is thrown straight up.
Answer:
the answer is B.
Explanation:
The ball that is thrown straight up has more kinetic energy and more speed than the ball that is thrown straight down. Both balls have the same kinetic energy and speed.
What is the kinetic energy and potential energy?The kinetic energy of a body can be determined as the energy of a moving physical system because of its motion. Work has to be done on an object to change its kinetic energy.
The kinetic energy of the moving system can be expressed as K.E. = ½mv² where ‘m’ is mass while ‘v’ is the velocity of the object.
The potential Energy of the physical system can be described as the energy stored due to its position. The mathematical formula for the calculation of the potential energy can be expressed in the form of P.E = m×g×h where ‘g’ is the gravitational acceleration, ‘m’ is the mass and ‘h’ is the height in meters
When two identical balls are thrown from a cliff, each with the same speed. One ball is thrown straight up, and the other ball is straight down. Both balls will have the same kinetic energy as well as speed.
Learn more about kinetic energy and potential energy, here:
brainly.com/question/15764612
#SPJ2
A heater marked 60w evaporates 6×10^-3kg of boiling water in 60secs what is the specific latent heat of vaporization of water in jkg^-1
Explanation:
Latent heat of evaporation is the heat required to change water to vapor at the same temperature boiling temperature.(100°C)
That water turns into vapor when heated at temperature more than 100°C without any increase in temperature.
that is latent heat of vaporization Q = mL
Roark saw Alejandro sitting by himself in the quad and leaning over, with his head resting on the heels of his hands. Roark approached him and said, "Hey Alejandro, you look sad." Alejandro responded, "Huh? No, I'm just thinking." Which difficulty in interpreting nonverbal behavior does this exchange exemplify?
A. Nonverbal messages are often ambiguous.
B. Nonverbal messages are continuous.
C. Nonverbal cues are multichanneled.
D. Nonverbal interpretation is culture-based.
Answer:
Option A
Explanation:
Nonverbal communications are ambiguous because some times the face expressions (non verbal signals – Sad face or sitting alone gesture of Alejandro) and the verbal signals (communication between Roark and Alejandro) do not match or contradict each other. Some people prefer to believe on their interpretations of the nonverbal signals as compared to that of the verbal signals
Hence, option A is correct.
answer this question for brainlest and 20 points
pls help me out i need help
Answer:
Angle of incidence. = Angle of reflection
0° = 0°
30°. = 30°
42°. =. 42°
60°. =. 60°
90°. =. 90°
angle of incidence is always equal to angle of reflection on plane surface
Hope it helps
600.0 mL of air is at 27.0 °C. What is the
volume at 60.0 °C?
[4 marks]
22. Compare and contrast the structure and roles of tendons and ligaments.
Answer:
Tendons: Tendons are cord-like, strong, inelastic structures that join skeletal muscles to bones
ligaments: Ligaments are elastic structures which connect bones to bones in joints.
Explanation:
If an object has a potential energy of 15 J and a kinetic energy of 20 J. What is the mechanical energy of the object?
Answer:
Mechanical energy = 35 Joules
Explanation:
Energy can be defined as the ability (capacity) to do work. The two (2) main types of energy are;
a. Potential energy (P.E): it is an energy possessed by an object or body due to its position above the earth.
b. Kinetic energy (K.E): it is an energy possessed by an object or body due to its motion.
Furthermore, the mechanical energy of a physical object or body is the sum of the potential energy and kinetic energy possessed by the object or body.
Mathematically, it is given by the formula;
Mechanical energy = P.E + K.E
Given the following data;
Potential energy = 15 J
Kinetic energy = 20 J
To find the mechanical energy;
Mechanical energy = P.E + K.E
Mechanical energy = 15 + 20
Mechanical energy = 35 Joules
Answer:
Mechanical energy = 35 Joules
Explanation:
3. a) Your body is made up of several simple machines that help you move. Identify three
parts of your body that act as simple machines. Identify the kind of machine for each one
and explain what it does.
Answer:
Explained below
Explanation:
1) The human arm: This is a type of simple machine called "Lever". In this type of machine, the elbow acts as the fulcrum, the palm serves as the load because that's where we place the load we want to carry. While the inner part of the arm which is the inner part of the elbow represents the effort because that is the joint we mover when making use of our arms.
2) Pulleys: An example of this in the human body is the knee cap where the direction of an applied force is changed. Thus means as it is in motion, it alters the direction for which the quadriceps tendon pulls on the tibia.
3) wheel and axle: An example of this in the human body is the lateral rotation of the shoulder joint medial. The humerus which is the bone between the shoulder and elbow will act as the axle while the rotator will be the will because when it is rotated a little bit, the humerus will move along with it.
