Chapter 5: Circular Motion, the Planets, and Gravity
1. An object weighs 20 Newtons on Earth. What is its approximate mass ?
A. 2 kg.
B. 20 g.
C. 10 kg.
D. 196 kg.
E. 640 kg.
2. Which of the following is NOT a vector?
A. acceleration
B. weight
C. mass
D. velocity
E. All of the above.
3. Two cars are moving around a circular track at the same constant speed. If car 1 is at the inner edge of the track and car 2 is at the outer edge, then
A. the acceleration of car 1 is less than the acceleration of car two.
B. the accelerations of both cars are equal and greater than zero.
C. the acceleration of car 1 is greater than the acceleration of car 2.
D. the accelerations of both cars are zero.
4. A car travels around a curve with constant speed. The correct statement from the following is:
A. The velocity of the car is constant.
B. The car has an acceleration directed inward toward the center of the curve.
C. The car has an acceleration directed outward from the center of the curve.
D. The car has zero acceleration.
E. The car has an acceleration directed in the instantaneous direction of the velocity vector.
5. A ball is whirled on the end of a string in a horizontal circle at constant speed. Suddenly, the string breaks. Immediately after the string breaks, the ball will
A move horizontally outward from the center of the circle.
B. move horizontally inward toward the center of the circle.
C. drop straight down.
D. have a horizontal velocity that is tangential to the circle.
6. Car A travels with speed v around curve number one, which has a radius r. Car B travels with speed 2v around curve number two, which has a radius 2r. The acceleration will be
A. zero for both cars.
B. the same for both cars.
C. greater for car A.
D. greater for car B.
7. If a ball at the end of a string is whirled in a vertical circle at constant speed, the tension will be
A. the same throughout the motion.
B. greatest at the lowest point in the motion.
C. greatest at the highest point in the motion.
D. greatest at a point where the string is instantaneously parallel to the ground.
ANSWERS: A C C B D D B