Chapter 9 Equation Practice                                                     Name ____________________________________

Here are the equations in Chapter 9

                                          

 

                               

1. What do the symbols mean, and what units are they measured in?

Symbol

Meaning

Units

W

 

 

F

 

 

d

 

 

t

 

 

PE

 

 

m

 

 

g

 

 

h

 

 

v

 

 

2. Which two equations could you use to find work?

3. How could you decide which one to use?

4. A crane uses 5200 N to lift a beam 5 meters. How much work did it do?

Given and unknown

Equation

Solve

5. The brakes on a bicycle do 125 N of work for 10 meters to stop the bicycle. How much work do the  brakes do?

Given and unknown

Equation

Solve

6. A jack uses 5000 J to lift a car 3 m off the ground in 4 seconds. How much power did it exert?

Given and unknown

Equation

Solve

7. You use 12 N of force to move a box 4 meters in 6 seconds. What was your power output?

Given and unknown

Equation

Solve

8. How much potential energy does a 70 kg pole vaulter have when he is 6 m off the ground?

Given and unknown

Equation

Solve

9. How much energy does a 2.5 kg book 2.0 m off the ground have?

Given and unknown

Equation

Solve

10. How much kinetic energy does a bullet with a mass of 0.02 kg have when it is moving at 200 m/s

Given and unknown

Equation

Solve

11. How much kinetic energy does the pole vaulter above have when he was moving down the track at 20m/s?

Given and unknown

Equation

Solve

12. How high off the ground does a 5 kg ball have to be to have 100 J of energy?

Given and unknown

Equation

Solve