Name
APS
Date
Mrs. Jiménez
Using Newton’s 2nd Law to Calculate Different Variables
You must write list all variables with units (including unknown) to the left to begin. Then you
must select the proper equation and then rearrange the equation so that it is solved for the
unknown. Then you must substitute in with units, and solve and then round to sig figs as you
normally would.
Fnet = ma
p = mv
∆p = m(vf-vi)
a = (vf-vi)/t
v = d/t
1. Your bicycle has a mass of 9.1 kilograms. You hit the brakes, causing the bicycle to
slow down at a rate of -1.79 m/s2. Calculate the net force that is decelerating the
bicycle.
2. The Space Shuttle has a liftoff mass of 2,041,000 kg and accelerates at a rate of 16
m/s2. Calculate the force (thrust) that is accelerating the Space Shuttle.
3. A runner has a mass of 89 kilograms. He produces a force of 84 Newtons between
the ground and his running shoes. How fast does he accelerate?
4. Two people are pushing a disabled car. One exerts a force of 200 N east, the other a
force of 150 N east. What is the net force exerted on the car? (No calculation needs
to be shown.)
5. Calculate the acceleration of a car if the force on the car is 450 Newtons and the mass
is 1300 kilograms.
6. What is the mass of a box if it takes 27 N of force to accelerate it at a rate of 2.6 m/s2?
7. CHALLENGE: What is the force exerted on a shopping cart if it weighs 12.6 kg and
it is accelerated from rest to 3.5 m/s in 8.5 seconds. Hint: Think back to mechanics
equations.
8. Two teams were having a tug of war. Team A had four people on the team, and each
of them pulled with 25N of force. Team B had three people on the team, and each of
them pulled with 35 N of force. Which team won, and what how much greater was
their net force on the rope? (No calculation needs to be shown.)