A disk is free to rotate on a fixed axis. A force of given magnitude F, in the plane of the disk, is to be applied. Of the following alternatives the greatest angular acceleration is obtained if the force is: 

A. applied tangentially halfway between the axis and the rim 

B. applied tangentially at the rim 

C. applied radially halfway between the axis and the rim 

D. applied radially at the rim 

E. applied at the rim but neither radially nor tangentially

The magnitude of the acceleration of a point on a spinning wheel is increased by a factor of 4 if: 

A. the magnitudes of the angular velocity and the angular acceleration are each multiplied by a factor of 4 

B. the magnitude of the angular velocity is multiplied by a factor of 4 and the angular acceleration is not changed 

C. the magnitudes of the angular velocity and the angular acceleration are each multiplied by a factor of 2 

D. the magnitude of the angular velocity is multiplied by a factor of 2 and the angular acceleration is not changed 

E. the magnitude of the angular velocity is multiplied by a factor of 2 and the magnitude of the angular acceleration is multiplied by a factor of 4

If the angular velocity vector of a spinning body points out of the page then, when viewed from above the page, the body is spinning: 

A. clockwise about an axis that is perpendicular to the page 

B. counterclockwise about an axis that is perpendicular to the page 

C. about an axis that is parallel to the page 

D. about an axis that is changing orientation 

E. about an axis that is getting longer

A pulley with a radius of 3.0 cm and a rotational inertia of 4.5×10⁻³ kg · m² is suspended from the ceiling. A rope passes over it with a 2.0-kg block attached to one end and a 4.0-kg block attached to the other. The rope does not slip on the pulley. At any instant after the blocks start moving, the object with the greatest kinetic energy is: 

A. the heavier block 

B. the lighter block 

C. the pulley 

D. either block (the two blocks have the same kinetic energy) 

E. none (all three objects have the same kinetic energy)

A force with a given magnitude is to be applied to a wheel. The torque can be maximized by: 

A. applying the force near the axle, radially outward from the axle 

B. applying the force near the rim, radially outward from the axle 

C. applying the force near the axle, parallel to a tangent to the wheel 

D. applying the force at the rim, tangent to the rim 

E. applying the force at the rim, at 45◦ to the tangent

A block is attached to each end of a rope that passes over a pulley suspended from the ceiling. The blocks do not have the same mass. If the rope does not slip on the pulley, then at any instant after the blocks start moving, the rope: 

A. pulls on both blocks, but exerts a greater force on the heavier block 

B. pulls on both blocks, but exerts a greater force on the lighter block 

C. pulls on both blocks and exerts the same magnitude force on both 

D. does not pull on either block 

E. pulls only on the lighter block

A disk starts from rest and rotates around a fixed axis, subject to a constant net torque. The work done by the torque during the second 5 s is as the work done during the first 5 s. 

A. the same 

B. twice as much 

C. half as much 

D. four times as much 

E. one-fourth as much 

A car travels north at constant velocity. It goes over a piece of mud, which sticks to the tire. The initial acceleration of the mud, as it leaves the ground, is: 

A. vertically upward 

B. horizontally to the north 

C. horizontally to the south 

D. zero 

E. upward and forward at 45^◦ to the horizontal

A disk starts from rest and rotates about a fixed axis, subject to a constant net torque. The work done by the torque during the second revolution is as the work done during the first revolution. 

A. the same 

B. twice as much 

C. half as much 

D. four times as much 

E. one-fourth as much 

The rotational inertia of a wheel about its axle does not depend upon its: 

A. diameter 

B. mass 

C. distribution of mass 

D. speed of rotation 

E. material composition