Newton’s Laws Problem Set
1. Draw a FBD for each of the following. Use an arrow to indicate the object’s direction of
motion (if any). In each case, be sure to (a) label the force(s) appropriately and (b) indicate
which forces that are equal.
a) A ball is rising vertically against air resistance.
b) A car is driving up a ramp.
c) A crate is being dragged along a floor by a rope at a constant speed.
2. Which of the following has more inertia: a Smart car, a person, or textbook? Explain your
answer.
3. What unbalanced force would be required to accelerate a 0.50 kg ball at 6.5 m/s 2?
4. What acceleration would an unbalanced force of 85 N produce on an object with a mass
of 7.2 kg?
5. Calculate the unbalanced force acting on a 4000 kg truck that changes its velocity from
22.0 m/s [N] to 8.00 m/s [N] in 4.5 s.
6. Mabel and Dipper are arguing over a toy. One pulls on the toy with a force of 34 N [R]. The
other pulls with a force of 30 N [L]. If the toy has a mass of 450 g, what will be its resulting
acceleration? Be sure to include a FBD of the situation.
7. Two toy ducks, attached to each other by a string are being pulled by a very happy elf
named Elfo who just got them as a present. The front duck is 5.0 kg and the back duck is
2.0 kg. If Elfo pulls them with a force of 15 N and there is no friction, calculate:
a) the acceleration of both ducks.
b) the tension in the string connecting duck 1 and duck 2.
8. A 1.2 kg ball is tossed straight up with a velocity of 6.7 m/s, encountering a force of air
resistance of 1.4 N.
a) Draw a free-body diagram for this ball.
b) Calculate the average net force experienced by the ball.
c) Calculate the average acceleration of the ball.
d) How high will the go?