AP Quiz Rotational motion Version 1

A solid disk with radius R, mass M, and moment of inertia I=½ MR2, rolls along a surface (without slipping) at constant velocity v. What is the angular momentum of the disk about its own axis as it rolls?

• MRv

• MRv/2

• 2MRv

• Mω

• Mω/2

The pulley system consists of two solid disks of different radii fastened together coaxially, with two different masses connected to the pulleys as shown above. Under what condition will this pulley system be in static equilibrium?

• m = M

• rm = RM

• r²m = R²M

• Rm=rM

• r² M= R² m

A horizontally-mounted disk with moment of inertia I spins about a frictionless axle. At time t=0, the initial angular speed of the disk is ω. A constant torque ፒ is applied to the disk, causing it to come to a halt in time t. How much Power is required to dissipate the wheel’s energy during this time?

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Two masses are connected by a light cord and hung from a frictionless pulley of negligible mass as shown. Mass m₁=3.00 kg, and mass m₂=2.00 kg. When the two masses are released from rest, the resulting acceleration of the two masses is approximately:

• 1 m/s²

• 2 m/s²

• 4 m/s²

• 6 m/s²

• 8 m/s²

A series of wrenches of different lengths is used on a hexagonal bolt, as shown below. Which combination of wrench length and force applies the greatest torque to the bolt?

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A cylinder of mass m and radius R has a moment of inertia of 1/2 mR². The cylinder is released from rest at a height h on an inclined plane, and rolls down the plane without slipping. What is the velocity v of the cylinder when it reaches the bottom of the incline?

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An asteroid traveling through space collides with one end of a long, cylindrical satellite as shown above, and sticks to the satellite. Which of the following is true of the isolated asteroid-satellite system in this collision?

• Kinetic energy K is conserved

• Total Energy E is conserved, but angular momentum L is not conserved

• Angular momentum L is conserved, but linear momentum p in not conserved

• Angular momentum L is conserved, and total energy E is conserved

• Linear momentum p is conserved but angular momentum L is not conservered

An amusement park ride consists of a large spinning cylinder of radius r with rough walls. At a given angular velocity ω the horizontal floor of the cylinder drops, but a rider of mass m remain safely pinned against the walls of the cylinder. What is the minimum coefficient of the static friction μ necessary for the rider to keep from sliding down the wall?

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A long, thin rod with moment of inertia I=2 kg m² is free to rotate about an axis passing through the midpoint of the rod. The rod begins rotating from rest at time t=0 seconds, accelerating constantly so that it has a rotational velocity of 4ㄫ rad/s after rotating through two complete revolutions. What is the rod's angular momentum at this point?

• 2ㄫ kg m²/s

• 8ㄫ kg m²/s

• 8 kg m² /s

• 4ㄫ kg m²

• 4 kg m²

A rigid bar with a weight of 100 Newtons is free to rotate about a frictionless hinge at a wall, and supported in a horizontal position by a spring scale attached to the ceiling at an angle of 30⁰ to the vertical, as shown. What force of tension is indicated by the spring scale?

• 100N

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• 50N