Exam 10: Conservation of Angular Momentum

A man turns with an angular velocity on a rotating table, holding two equal masses at arms' length. If he drops the two masses without moving his arms, his angular velocity

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Question 21

Let us compare the angular momentum of Mars (L_M) in its orbit around the Sun to that of Earth (L_E). The mean orbital speed of Mars is 24 km/s, whereas that of Earth is 30 km/s. The mean orbital radius of Mars is 228 $\times$ 10⁶ km, whereas that of Earth is 150 $\times$ 10⁶ km. If the mass of Mars is 11% that of Earth, calculate the ratio L_M / L_E.

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Question 22

The velocity a planet of mass m with circular orbit is given by $The velocity a planet of mass m with circular orbit is given by where vo in m/s is a constant, and \omega is the angular velocity. Its position vector is .The angular momentum of the planet about the center of the orbit is$ where v_o in m/s is a constant, and $\omega$ is the angular velocity. Its position vector is $The velocity a planet of mass m with circular orbit is given by where vo in m/s is a constant, and \omega is the angular velocity. Its position vector is .The angular momentum of the planet about the center of the orbit is$ .The angular momentum of the planet about the center of the orbit is

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Question 23

Two balls, each of mass m, are attached to the ends of a rod of length l and mass M. The system is then rotated about a frictionless pivot located at the center of mass with angular velocity $\omega$ . The angular momentum of the system in vector form about the pivot is $Two balls, each of mass m, are attached to the ends of a rod of length l and mass M. The system is then rotated about a frictionless pivot located at the center of mass with angular velocity \omega . The angular momentum of the system in vector form about the pivot is$

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Question 24

If the angular momentum of a system is constant, which of the following statements must be true?

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Question 25

If the sum of the torques on a body about a fixed axis is not zero, the body most certainly

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Question 26

A disc with moment of inertia I₁ = 40 kg.m² and angular velocity $\omega$ ₁ = 20 rad/s is dropped on to a stationary second disc along the axis of rotation. The second disc has moment of inertia I₂ = 60 kg.m². What is the angular velocity of the two discs?

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Question 27

Which of the following statements is true?

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Question 28

The figure shows vectors representing the angular velocity of precession $\omega$ _p and the spin velocity $\omega$ _s. The associated torque vector points along which of the axes? $The figure shows vectors representing the angular velocity of precession \omega p and the spin velocity \omega s. The associated torque vector points along which of the axes?$

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Question 29

A wheel is rotating freely with an angular speed of 20 rad/s on a shaft whose moment of inertia is negligible. A second identical wheel, initially at rest, is suddenly coupled to the same shaft. The angular speed of the coupled wheels is

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Question 30

For a rotating molecule with a constant moment of inertia what is the energy difference between the l = 5 and l = 7 energy levels?

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Question 31

If an object were to suddenly shrink and decrease its moment of inertia by a factor of 3, what is the difference in energy between the final and initial rotational kinetic energies?

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Question 32

Coriolis acceleration is a result of fictitious force when an observer is in a rotating frame. It is expressed as where is the angular velocity of the rotating frame and is the velocity of an object in the rotating frame. Suppose and what is ?

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Question 33

Which of the following statements is not true?

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Question 34

A wheel is set spinning and is then hung by a rope placed at one end of the axle. If the wheel is spinning as shown, the angular momentum of the wheel could be represented by vector

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Question 35

Use the figure to the right to answer the next problem. A ball of mass of mass m is tied with a light string to a vertical post of radius R_p and slides on a frictionless horizontal surface. As the ball travels around the post, the string wraps around the post, shortening the length. At t = 0 s, its speed is v_o and radius is r_o. -What is the angular momentum of the ball after the string has wrapped once around the post?

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Question 36

Two wheels with identical moments of inertia are rotating about the same axle. The first is rotating clockwise at 2.0 rad/s, and the second is rotating counterclockwise at 6.0 rad/s. If the two wheels are brought into contact so that they rotate together, their final angular velocity will be

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Question 37

In a rotating atomic nucleus shaped like a football the quantized rotational energy levels have angular momentum values l = 0, 2, 4, 6, 8, etc. Given that the energy of each level is equal to a constant times l $\times$ (l + 1), calculate the ratio of the l = 4 to l = 2 energy levels.

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Question 38

Particles 1, 2, and 3 have equal masses and equal speeds. The angular momentum with respect to the origin for these three masses is

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Question 39

A wheel is rotating in the direction indicated. If you pull down on the end of the axle nearest you, that end of the axle tends to move

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Question 40

Showing 21 - 40 of 67

A man turns with an angular velocity on a rotating table, holding two equal masses at arms' length. If he drops the two masses without moving his arms, his angular velocity

If the angular momentum of a system is constant, which of the following statements must be true?

If the sum of the torques on a body about a fixed axis is not zero, the body most certainly

A disc with moment of inertia I₁ = 40 kg.m² and angular velocity $\omega$ ₁ = 20 rad/s is dropped on to a stationary second disc along the axis of rotation. The second disc has moment of inertia I₂ = 60 kg.m². What is the angular velocity of the two discs?

Which of the following statements is true?

A wheel is rotating freely with an angular speed of 20 rad/s on a shaft whose moment of inertia is negligible. A second identical wheel, initially at rest, is suddenly coupled to the same shaft. The angular speed of the coupled wheels is

For a rotating molecule with a constant moment of inertia what is the energy difference between the l = 5 and l = 7 energy levels?

If an object were to suddenly shrink and decrease its moment of inertia by a factor of 3, what is the difference in energy between the final and initial rotational kinetic energies?

Coriolis acceleration is a result of fictitious force when an observer is in a rotating frame. It is expressed as where is the angular velocity of the rotating frame and is the velocity of an object in the rotating frame. Suppose and what is ?

Which of the following statements is not true?

A wheel is set spinning and is then hung by a rope placed at one end of the axle. If the wheel is spinning as shown, the angular momentum of the wheel could be represented by vector

Two wheels with identical moments of inertia are rotating about the same axle. The first is rotating clockwise at 2.0 rad/s, and the second is rotating counterclockwise at 6.0 rad/s. If the two wheels are brought into contact so that they rotate together, their final angular velocity will be

In a rotating atomic nucleus shaped like a football the quantized rotational energy levels have angular momentum values l = 0, 2, 4, 6, 8, etc. Given that the energy of each level is equal to a constant times l $\times$ (l + 1), calculate the ratio of the l = 4 to l = 2 energy levels.

Particles 1, 2, and 3 have equal masses and equal speeds. The angular momentum with respect to the origin for these three masses is

A wheel is rotating in the direction indicated. If you pull down on the end of the axle nearest you, that end of the axle tends to move

Systems of Measurement

Motion in One Dimension

Motion in Two and Three Dimensions

Newtons Laws

Applications of Newtons Laws

Work and Energy

Conservation of Energy

Systems of Particles and Conservation of Linear Momentum

Rotation

Gravity

Static Equilibrium and Elasticity

Fluids

Oscillations

Wave Motion

Superposition and Standing Waves

Temperature and the Kinetic Theory of Gases

Heat and the First Law of Thermodynamics

The Second Law of Thermodynamics

Thermal Properties and Processes

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Exam 10: Conservation of Angular Momentum

A man turns with an angular velocity on a rotating table, holding two equal masses at arms' length. If he drops the two masses without moving his arms, his angular velocity

The velocity a planet of mass m with circular orbit is given by where vo in m/s is a constant, and ω\omegaω is the angular velocity. Its position vector is .The angular momentum of the planet about the center of the orbit is

Two balls, each of mass m, are attached to the ends of a rod of length l and mass M. The system is then rotated about a frictionless pivot located at the center of mass with angular velocity ω\omegaω . The angular momentum of the system in vector form about the pivot is

If the angular momentum of a system is constant, which of the following statements must be true?

If the sum of the torques on a body about a fixed axis is not zero, the body most certainly

A disc with moment of inertia I1 = 40 kg.m2 and angular velocity ω\omegaω 1 = 20 rad/s is dropped on to a stationary second disc along the axis of rotation. The second disc has moment of inertia I2 = 60 kg.m2. What is the angular velocity of the two discs?

Which of the following statements is true?

The figure shows vectors representing the angular velocity of precession ω\omegaω p and the spin velocity ω\omegaω s. The associated torque vector points along which of the axes?

A wheel is rotating freely with an angular speed of 20 rad/s on a shaft whose moment of inertia is negligible. A second identical wheel, initially at rest, is suddenly coupled to the same shaft. The angular speed of the coupled wheels is

For a rotating molecule with a constant moment of inertia what is the energy difference between the l = 5 and l = 7 energy levels?

If an object were to suddenly shrink and decrease its moment of inertia by a factor of 3, what is the difference in energy between the final and initial rotational kinetic energies?

Coriolis acceleration is a result of fictitious force when an observer is in a rotating frame. It is expressed as where is the angular velocity of the rotating frame and is the velocity of an object in the rotating frame. Suppose and what is ?

Which of the following statements is not true?

A wheel is set spinning and is then hung by a rope placed at one end of the axle. If the wheel is spinning as shown, the angular momentum of the wheel could be represented by vector

Two wheels with identical moments of inertia are rotating about the same axle. The first is rotating clockwise at 2.0 rad/s, and the second is rotating counterclockwise at 6.0 rad/s. If the two wheels are brought into contact so that they rotate together, their final angular velocity will be

In a rotating atomic nucleus shaped like a football the quantized rotational energy levels have angular momentum values l = 0, 2, 4, 6, 8, etc. Given that the energy of each level is equal to a constant times l ×\times× (l + 1), calculate the ratio of the l = 4 to l = 2 energy levels.

Particles 1, 2, and 3 have equal masses and equal speeds. The angular momentum with respect to the origin for these three masses is

A wheel is rotating in the direction indicated. If you pull down on the end of the axle nearest you, that end of the axle tends to move

Systems of Measurement

Motion in One Dimension

Motion in Two and Three Dimensions

Newtons Laws

Applications of Newtons Laws

Work and Energy

Conservation of Energy

Systems of Particles and Conservation of Linear Momentum

Rotation

Gravity

Static Equilibrium and Elasticity

Fluids

Oscillations

Wave Motion

Superposition and Standing Waves

Temperature and the Kinetic Theory of Gases

Heat and the First Law of Thermodynamics

The Second Law of Thermodynamics

Thermal Properties and Processes

Filters

A disc with moment of inertia I₁ = 40 kg.m² and angular velocity $\omega$ ₁ = 20 rad/s is dropped on to a stationary second disc along the axis of rotation. The second disc has moment of inertia I₂ = 60 kg.m². What is the angular velocity of the two discs?

In a rotating atomic nucleus shaped like a football the quantized rotational energy levels have angular momentum values l = 0, 2, 4, 6, 8, etc. Given that the energy of each level is equal to a constant times l $\times$ (l + 1), calculate the ratio of the l = 4 to l = 2 energy levels.