1. Physical Science Review #2 motion & force

2. Concept Questions Distance: how far you travel
Does NOT need to be in a straight line
Displacement: change in position
Must be in a straight line
Must be in a particular direction
If you end up where you started, displacement = 0
Speed: how fast you go
Velocity: how fast you go in a direction

3. Concept Questions Acceleration: how much your speed changes
When its positive, you’re speeding up
When its negative, you’re slowing down
Force- a push or a pull on an object
Mass- never changes
Weight- a force that depends on gravity, it can change
Inertia-the resistance of an object to being moved
Increases as Mass Increases!

4. Concept Questions- Newton’s Laws
First: things at rest tend to stay at rest, things in motion tend to stay in motion until moved by a different force
Second: As you increase force, acceleration goes up. As you increase mass, acceleration goes down
Third: Every action has an opposite and equal reaction

5. Concept: Impulse and Momentum
Momentum= Inertia in motion
An object with a lot of momentum is hard to stop
Impulse=What changes momentum
Greater impulse if greater force and greater time
To decrease the effect of force, time must be increased
To increase the effect of force, time must be decreased
Two types of collisions:
Elastic-objects bounce off each other
Inelastic-object stick together

6. Concept Questions
Conservation of momentum: you can’t create or destroy momentum, but you can transform it. If you start out with 100 units, you have to end with 100 units.
Air Resistance is why things fall at different rates. If there was no air resistance, everything would fall exactly at the same acceleration and hit the ground at the same time.

7. Concept questions-Graphs
Distance-Time graphs
Slope=speed
If slope is a flat line means you are going no where
If slope increases you are increasing speed
If slow decreases you are decreasing speed
Velocity-Time graphs
Slope=acceleration
If slope is a flat line, you have constant speed
If slope is increasing, you are increasing acceleration
If slope is decreasing you are decreasing acceleration

8. Resulting Amount of Force?
Force Diagrams:
Forces Present:
Resulting Amount of Force?
Will there be motion?
If Yes, What direction?

9. Math Stuff You will get all triangles on exam!
If you are solving for the top of the triangle multiply what is beside each other
If you are solving for something on the bottom of the triage, divide top by bottom
How do you know you will solve for distance?
How do you know you will solve for time?

10. Math stuff-Chapter 10&11 d=distance v=velocity t=time a=acceleration
(m/s)
t=time
(s)
a=acceleration
(km/hr2, m/s2)
vi=initial velocit
Vf=final velocity
Remember, if something is stopped or at rest or stationary, its velocity is zero
F=Force (N)
m=mass (kg)
p=momentum
(kg * m/s)
I=impulse (kg*m/s)