CP Physics Study Guide - Forces
2014
Smith
Name : ________________________
Anything in your notebook from page 33 to page 56 is possibly on the test.
Topics Covered/explained/give examples/ be able to explain which law applies
-
Newton’s first law
-
Newton’s second law
-
Newton’s third law
What is the point of a free body diagram and when do you use them?
For the following know the definition, the units and whether it is a scalar or a vector.
Know how the moving object lab related to Newton’s Laws
Be able to describe your rocket and what the purpose is of each item on the rocket.
Explain the difference between mass and weight.
Why does a suitcase seem easier to move when you pull up on it?
Why are you feel heavier when an elevator first accelerates?
What is the difference between static and kinetic friction? What makes it different?
VOCABULARY
Force
Mass
Weight
Inertia
Gravity
Net force
Applied Force
Normal Force
Push
Pull
Constant velocity
Rest
Static Friction
Sliding or Kinetic Friction
Retarding Force
Equilibrium
Free Body Diagram
Coefficient of friction
Types of problems
- Be able to do these problems conceptually and with numbers
1. A box pulled to the right, no
friction
2. A box pulled to the right,
accelerating, friction
3. A box pulled to the right,
friction, constant velocity
4. A box pulled to the right at a
45 degree angle, no friction
5. A box pushed down to the
right at a 45 degree angle, no
friction
6. A box pulled to the right at a
45 degree angle, friction
7. A box pushed down to the
right at a 45 degree angle,
friction
8. A box in an elevator,
accelerating up
9. A box in an elevator,
accelerating down
Show Fg Fn Fa Ff when appropriate . Be sure that your arrows are drawn proportionally. Assume the mass
of the box if 5kg in each case.
Possible exam questions
1.) An object has a mass of 45 kg. What is its weight on earth? What is its weight on the moon?
2a. ) Draw a free body diagram of the following scenario. Andrew is pushing a crate with a mass of 25 kg with
115 N going north while Ricky is pushing the crate going 100 N south.
2b.) What is the net force of the above problem assuming no friction?
2c.) What is the acceleration?
3.) Calculate the force it will take to get a 25 kg crate to slide. 𝜇 s is 0.35 and 𝜇 k is 0.20 . Predict what will
happen if 100 N is applied. Be as specific as possible. Draw a free body diagram.
4.) Give an example when the normal force is not the opposite direction of the gravitational force?
5a.) 35 N is pulling to the left and friction opposes with 15N. Find the net force and show the free body
diagram.
5b.) Find the acceleration and the direction of a 4 kg object for 5a.
6.) A 35kg bike accelerates at 5m/s 2. With what force was the person pedaling?
7. Find the weight and mass of a 32 N object.
Physics
Basic Reference Chart
Name
Displacement
Acceleration
Velocity
Volume
Weight
Time
Force
Position
Mass
Symbol
for term
SI unit for
term
Vector or
scalar
Definition