Unit 8 - Energy, Work, and Power

Question 1

Whats the formula for kinetic energy?

Answer 1

1/2mv** (1/2 x mass x volume squared)

Question 2

whats the formula for gravitational potential energy?

Answer 2

mgh (mass x gravity x height change)

Question 3

Whats the formula for work done?

Answer 3

fd (force x displacement moved by the force)
or
(weight x vertical distance moved)

Question 4

what is energy?

Answer 4

the ability of a body to perform work

Question 5

what is the principle of conservation of energy?

Answer 5

the total energy of a system always remains constant but it can change from 1 form to another

Question 6

what is kinetic energy?

Answer 6

the energy possessed by moving objects

Question 7

what is potential energy?

Answer 7

the energy possessed by objects due to their position or configuration

Question 8

what is gravitational potential energy?

Answer 8

energy possessed by objects due to their height from the surface of the earth

Question 9

what is elastic potential energy?

Answer 9

energy possessed by objects due to stretch / energy possessed by strained objects

Question 10

what is electric potential energy?

Answer 10

positive and negative attraction / the energy acquired by the charged particles in electric field

Question 11

whats the formula for mechanical energy?

Answer 11

KE + (G)PE

Question 12

what are the 3 types of potential energy?

Answer 12

-gravitational potential energy
-elastic potential energy
-electric potential energy

Question 13

what is work done equal to?

Answer 13

energy transferred

Question 14

what is 1 joule?

Answer 14

the energy transferred (work done) by a force of 1N when it moves through a distance of 1m

Question 15

what is power?

Answer 15

the rate at which energy is transferred, or the rate at which work is done (how fast work is done)

Question 16

what is efficiency?

Answer 16

how much useful work is done in a given time without wasting much energy

Question 17

whats the formula for efficiency (energy)

Answer 17

useful work done/total energy input

Question 18

whats the formula for efficiency (power)

Answer 18

useful power output/total power

Question 19

whats the formula for useful power output?

Answer 19

force x speed

Question 20

whats the relationship (triangle) for work done (energy), power, and time?

Answer 20

top: work done (energy)
bottom 2: power and time

Question 21

whats the unit for power?

Answer 21

watts (W)

Question 22

1W=?

Answer 22

1J/s

Question 23

What is renewable fuel?

Answer 23

Fuel that once used, more can grow/be made to replace the used up fuel

Question 24

What is non renewable fuel?

Answer 24

Fuel that cannot be replaced

Question 25

What are 2 examples of non renewable energy resources?

Answer 25

Fossil fuels
Nuclear fuels

Question 26

What are 7 examples of renewable energy resources?

Answer 26

Hydroelectric energy
Tidal energy
Wind energy
Wave energy
Geothermal energy
Solar energy
Biofuels

Question 27

What are 4 problems for non renewable energy resources?

Answer 27

Supplies are limited
Carbon dioxide pollutes causing global warming
Expensive
Dangerous

Question 28

What are what are 3 prpblems for renewable energy resources?

Answer 28

Difficult to build
Expensive
Spoils landscape/causes environmental damage