Physics
Vandebilt Catholic High School
W. Dupre

Newton’s Laws of Motion

Additional Practice Problems

  1. A 60 kg boy and a 40 kg girl use an elastic rope while engaged in a tug-of-war on an icy frictionless surface. If the acceleration of the of the girl toward the boy is 3.0 m/s2, determine the magnitude of the acceleration of the boy toward the girl.

    2. Ans. 2.0 m/s2

  2. If you use a horizontal force of 30 N to slide a 12 kg crate across the floor at a constant velocity, what is the force of friction between the crate and the floor?

    3. Ans. 30 N

  3. If a 40 N applied force only accelerates a 5.0 kg mass at a rate of 6 m/s2 along a horizontal surface, how large is the frictional force?

    4. Ans. 10 N

  4. A towrope is used to pull a car weighing 17150 N. What net force does the rope exert if the car’s acceleration is 1.35 m/s2?

    5. Ans. 2362.5 N

  5. A proton has a mass of 1.672 X 10-27 kg. What is its weight?

    6. Ans. 1.64 X 10-26 N

  6. In bench pressing 100 kg, a weight lifter applies a force of 1040 N. How large is the upward acceleration of the weights during the lift?

Ans. 0.6 m/s2