PSC 1121 Intro to Physical Science
1. Two men pull on a cart with a mass of 90 kg. If one man pulls 140 N to the right, and the other man pulls 195 N to the left, then find the magnitude and direction of the acceleration for the cart.
Answer: a = -0.611 m/s2 (to the left)
2. A boy pulls a 150 kg sled across the ice using a force of 20 N northward. What is the acceleration of the sled?
Answer: a = 0.133 m/s2
3. A 1500 kg truck traveling 20 m/s hits a 700 kg Volkswagon which is at rest (no external forces are present). If the two vehicles stick together afterward, what is the final velocity of the wreckage?
Answer: v = 13.6 m/s
4. A 0.28 kg football is kicked for a field goal. After it’s kicked, it speeds up from rest to 18 m/s.
a) What is the impulse imparted to the ball by the kicker’s foot?
Answer: I = 5.04 kg m/s
b) If the foot is in contact with the ball for 0.14 seconds, with what average force did it hit the ball?
Answer: F = 36 N
5. A 0.012 kg ping-pong ball is placed 1.8 m away from 0.3 kg billiard ball. Calculate the gravitational force between the two objects.
Answer: F = 7.41x10-14 N
6. A 0.005 kg golf ball is placed 0.4 m away from 0.8 kg pool ball. Calculate the gravitational force between the two balls.
Answer: F = 1.67x10-12 N
7. A 0.001 kg nail is placed 0.2m away from 0.1 kg hammer. Calculate the gravitational force on the nail from the hammer.
Answer: F = 1.67x10-13 N