Page 138 - Schaum's Outline of Theory and Problems of Applied Physics

CHAP. 10] ROTATIONAL MOTION 123

Multiple-Choice Questions

10.1. A particle the distance R from the axis of rotation of a spinning body has
(a) an angular velocity proportional to R
(b) an angular velocity proportional to 1/R
(c) a linear velocity proportional to R
(d) a linear velocity proportional to 1/R

10.2. A hoop and a disk of the same mass and radius roll down an inclined plane. At the bottom they have the same
(a) angular velocity (c) KE of rotation
(b) angular momentum (d) potential energy

10.3. A ball is swung in a circle at the end of a string. A property of the ball that does not depend on the length of the
string is its
(a) angular velocity (c) linear velocity
(b) angular momentum (d) centripetal acceleration

10.4. The ball of Question 10.3 does not have to possess
(a) angular velocity (c) angular acceleration
(b) angular momentum (d) centripetal acceleration

10.5. A quarter of a circle contains
(a) π/4 rad (c) π rad
(b) π/2 rad (d) 2π rad

10.6. An angle of π/18 rad is equivalent to

(a) 10 ◦ (c) 20 ◦
(b) 18 ◦ (d) 36 ◦

10.7. The linear velocity of the rim of a wheel 80 cm in diameter when the wheel turns at 90 rev/min is
(a) 0.6π m/s (c) 1.5π m/s
(b) 1.2π m/s (d) 2.4π m/s

10.8. In 30 s the crankshaft of a truck engine operating at 2400 rev/min turns through
(a) 382 rad (c) 3770 rad
(b) 1200 rad (d) 7540 rad

10.9. A pulley is uniformly accelerated from rest to an angular velocity of 30 rad/s in 8.0 s. The total angle through which
the pulley turned during the acceleration is
(a) 60 rad (c) 240 rad
(b) 120 rad (d) 3600 rad

10.10. A motor takes 6.0 s to go from 150 to 50 rad/s at constant angular acceleration. The total angle through which the
motor’s shaft turned during the acceleration is
(a) 300 rad (c) 1200 rad
(b) 600 rad (d) 3600 rad
10.11. A solid iron cylinder A rolls down a ramp, and an identical iron cylinder B slides down the same ramp without
friction.
(a) A reaches the bottom first.
(b) B reaches the bottom first.