Test Unit 7 Energy

Question 1

What is the potential energy of a puppy who eights 18N sitting in a high chair 2m high?

Answer 1

Find = GPE=?
Given = F=ma F=18N h = 2m
Formula = GPE=ham GPE=Fh
Substitute = GPE=18x2
Solve = GPE=36N

Question 2

If a 15 kg rock falls from a height of 10m and lands on a guy about 2.5 s later, how much power did it hit him with

Answer 2

Find = P=? W=?
Given = m=15g d=10m t=2.5s a=9.8m/s2
Formula = p=w/t w=Fd F=ma
Sub = F=15x9.8 w=147/10 p=14.7/2.5
Solve = p=5.88 W

Question 3

As the time required to do a given amount of work decreases the power developed

Answer 3

Increases

Question 4

What are two examples the same type of thermal energy transfer

Answer 4

Iron and ironing board

Stove and frying pan