Download Newton`s Laws and Force Study Guide The exam will consist of 18

Newton's Laws and Force Study Guide
The exam will consist of 18 multiple choice questions and 2 free response questions. One of the free
response questions will pertain to Newton’s Laws and the other free response question will pertain to
motion graphs.
Topics:
Newton's 1st Law and Inertia- Know what it means for an object to be in equilibrium. Be able to identify
which object has the most inertia when given different objects.
Newton's 2nd Law- Know how to calculate the net force using Fnet=ma. Also be able to find the net force
when given several forces acting on an object
Weight vs. Mass- Know how to calculate weight using Fg=mg. Know that weight is a force and mass is a
resistance to accelerate. Be able to explain the relationship between weight and mass.
Newton's Laws and their Applications to Elevators and Skydiving- Be able to apply Newton’s Laws to
systems like Elevators and Skydiving. For elevators, be able to identify the motion of the elevators when
given the magnitudes of the weight and normal force. For skydiving, be able to explain the motion of a
skydiver before and after hitting terminal velocity.
Newton's 3rd Law- Be able to explain Newton’s 3rd Law and identify action-reaction pairs.
Friction (Static Friction vs. Kinetic Friction, Calculating Friction using Ff =µFN)
Free-body Diagrams-Be able to draw free-body diagrams and determine whether an object is
accelerating from looking at its free-body diagram
Free Response Sample Questions:
1. A 2 kg wooden crate is pushed across a wooden floor with a force of 12 N. (Show all equations and
substitute with units)
a) Draw a free-body diagram showing all forces acting on the crate.
b) Calculate the weight of the crate.
c) Find the force of friction acting on the crate.
d) Find the net force acting on crate.
e) Calculate the acceleration of the crate.
2. A skier on waxed skis is pulled at constant speed across level snow by a horizontal force of 39
newtons. Calculate the normal force exerted on the skier. Show all work.
3. A 10 kg steel crate is moving at 3 m/s to the right. It slows down as it slides across a stainless steel
floor.
a) Draw a freebody diagram showing all forces acting on the crate.
b) Calculate the weight of the crate.
c) Find the force of friction acting on the crate.
d) What is the net force acting on crate?
e) Calculate the acceleration of the crate.
4. Find the force of friction acting on the 15 kg crate below if it accelerates at 2 m/s2 when pushed
forward by a force of 40 N.
40 N
2 m/s2