05 work, energy and power

Question 1

What are the two key types of energy for this chapter?

Answer 1

kinetic energy and gravitational potential energy.

Question 2

What is the equation for work done?

Answer 2

force x the distance moved in the direction of the force.

Question 3

What is the unit for work done?

Answer 3

joules, J

Question 4

What is another way o describing work done?

Answer 4

energy transferred.

Question 5

What is the equation for kinetic energy?

Answer 5

0.5m(v)squared.

Question 6

What is the equation for gravitational potential energy?

Answer 6

mgh.

Question 7

How do you display energy transfers?

Answer 7

By writing a word equation.

Question 8

What is power?

Answer 8

The rate of work done or doing work.

Question 9

What is the equation of power involving work done?

Answer 9

p=w/t or power=workdone/timw

Question 10

What is the unit of power?

Answer 10

Watts, W.

Question 11

What is the equation for efficiency?

Answer 11

useful power out / total power in x100

Question 12

What is the equation for power involving force?

Answer 12

p=fv, power=force x velocity. With force being the ‘driving force’

Question 13

Is power scalar or vector?

Answer 13

Scalar.