1. Physics White Board Review
Formula Practice

2. What are the units for force?
Newtons
What are the units for work?
joules
What are the units for mass?
grams
What are the units for acceleration?
m/s2
What are the units for distance?
Meters or centimeters

3. Example 1: Work Formula
The box to the left is pushed up the ramp. How much work was done to move the box up the ramp?
2 N
W=Fd
W = (2)(12)
Work = 24 joules

4. Example 2: Net Force Formula
10 kilograms
???
The above box accelerated 3.4 m/s2.What is the force that was applied to the above box?
F = ma
F = (10)(3.4)
F = 34 Newtons

5. Example 3: Average Speed Formula
The graph to the right shows the motion of a cat over time. What was the cats average speed?
S=d/t = 80/100
=0.8 m/s

6. What is the acceleration of the above box?
Example 4
10 kilograms
12 Newtons of force
What is the acceleration of the above box?
F=ma
12 = (10)(a)
1.2 m/s2

7. Example 5
Nicholas pushes a dirt bike up a ramp with a force of 225 N. He uses 1,125 joules of energy to get the bike up the ramp. How tall must the ramp have been?
W=Fd
1125 = (225)(d)
Height (distance) = 5 meters

8. What is the speed of the object after 6 seconds?
Example 6
What is the speed of the object after 6 seconds?
Time
(seconds)
Distance
(meters) 2 3 6 7 8 5
S= d/t
S = 3/6
0.5 m/s

9. Example 7
The graph to the right shows the motion of a cat over time. What was the cats speed for the first 40 seconds?
S = d/t = 20/40
0.5 m/s

10. Example 8
The graph to the right shows the motion of a cat over time. What was the cats speed between 40 and 60 seconds?
0 m/s …the cat isn’t moving!!!

11. Example 8
The chart below shows the mass of four different types of balls. Each ball is sitting on top of the ramp that is also shown below. Which ball would has the greatest potential energy while sitting on top of the ramp?
4 m
Ball A
Ball B
Ball C
Ball D
2 m
Ball
Material
Mass A
Metal
63 g B
Styrofoam
7.4 g C
Glass
59 g D
Plastic
9.2 g

12. Which of the following describes the energy transformations that takes place in a burning log?
Chemical energy to radiant and thermal energy
Chemical energy to electrical and thermal energy
Potential energy to chemical energy
Kinetic energy to radiant and thermal energy

13. Which of the diagrams show the conversion of chemical to mechanical energy?
1 and 2
1 and 3
2 and 4
3 and 4

14. Mrs. Tucker threaded a string through a straw, blew up a balloon and taped a balloon to a straw as shown below. When she releases air from the neck of the balloon what will happen?
Following Newton’s 2nd Law, the balloon and the straw will move toward point one.
Following Newton’s 1st Law, the balloon and straw will spin on the string.
Following Newton’s 3rd Law, the balloon and straw will move towards point 2.
Following Newton’s 1st Law, the balloon and straw will not move.

15. Biceps and triceps are muscles in the arm
Biceps and triceps are muscles in the arm. When biceps expand, triceps contract, allowing the arm to move. Which of Newton’s Laws of Motion best explains the forces at work by the muscles in the arm?
Newton’s 1st Law of inertia
Newton’s 2nd Law of force and acceleration
Newton’s 3rd Law of action-reaction
Newton’s Laws do not apply to human body parts.

16. When a car suddenly stops, the objects in the back seat are thrown forward. This is due to-
Newton’s 1st Law of Motion
Newton’s 2nd Law of Motion
Newton’s 3rd Law of Motion
The Universal Law of Gravitation

17. The tendency of an object to resist changes in its motion is related to one of Newton’s laws. It is called-
Acceleration
Force
Inertia
Work