Circle the right answers.

I. Which of the following objects (all with the same mass M) moves down an incline with the slowest speed:

A. A solid sphere of radius R rolls down the incline without slipping.

B. A solid cylinder of radius R rolls down the incline without slipping.

C. A hollow cylinder of radius R rolls down the incline without slipping.

D. A block slides down the incline without any friction.

E. A solid sphere of radius 0.5R rolls down the incline without slipping.

Ans. C

II. In the figure below, five forces act on a massless rod free to pivot at point P. Which force is producing a counter-clockwise torque about point P?

A. A

B. B

C. C

D. D

E. E

Ans. C

III. 1 g/cm³ equals to

A. 1000 Kg/m³

B. 10⁶ Kg/m³

C. 0.001 Kg/m³

D. 10^-6 Kg/m³

E. None of above

Ans. A

IV. One cubic centimeter of Lead (density ~11.3 gm/cm³), one cubic centimeter of Iron (density~7.8 gm/cm³), and one cubic centimeter of Aluminum (density~2.7 gm/cm³) are dropped into a pool, which has the largest buoyant force on it?

A. Lead

B. Iron

C. Aluminum

D. All are the same

E. Depends on the shape of the objects

Ans. D