Work, Energy, Power

Question 1

Define work

Answer 1

Forces causes an object to move through a distance, or change its position

Question 2

SI unit for work

Answer 2

Joule (J)

Question 3

Formula for work

Answer 3

W = F X x

Question 4

What does W stand for in work?

Answer 4

Work done in j

Question 5

What does F stand for in work?

Answer 5

Force applied in N

Question 6

What does x stand for in work?

Answer 6

Distance travelled in m

Question 7

How many joules cover one metre?

Answer 7

1 joule of work is the amount of work done to cover a distance of 1m in the direction of force when a force if 1N is applied to body

Question 8

List three requirements for work to be done?

Answer 8

1. Applied force
2. Object/body should move as a result of force
3. Object move in direction of force

Question 9

What is force done against?

Answer 9

Two forces - gravity + friction

Question 10

What does it mean when push against something and it does not move?

Answer 10

No work done - no motion

Question 11

What does it mean when you push something and moves by itself?

Answer 11

No work done over distance - no applied force

Question 12

What does it mean when you walk with something in your hand?

Answer 12

no work done - applied force and motion were not in same direction

Question 13

What must you calculate if work done in vertical plane?

Answer 13

Calculate weight before calculate work done

Question 14

vertical

Question 15

horizontal

Question 16

Define energy

Answer 16

Ability to do work

Question 17

SI unit for energy

Answer 17

Joule (J)

Question 18

How many forms of energy are there?

Answer 18

1. Chemical
2. Potential
3. Kinetic
4. Energy waves
5. Heat
6. Sound
7. Magnetism
8. Electrical
9. Nuclear

Question 19

Potential energy

Answer 19

Ep = m.g.h

Question 20

Kinetic energy

Answer 20

Ek = 1/2m .v2

Question 21

Electrical energy

Answer 21

E = I . V . T

Question 22

Define gravitational potential energy

Answer 22

Object is defined as the energy an object has because of its position in the field relative to some reference point

Question 23

Gravitational potential energy

Answer 23

Ep = mgh

Question 24

Ep stands for what in gravitational potential energy?

Answer 24

Gravitational potential energy - J

Question 25

m stands for what in gravitational potential energy?

Answer 25

mass of object (kg)

Question 26

g stands for what in gravitational potential energy?

Answer 26

acceleration due to gravity

Question 27

h stands for what in gravitational potential energy?

Answer 27

vertical height of the object from ground level

Question 28

Define kinetic energy

Answer 28

Of an object is the energy an object possesses as a result of its motion

Question 29

Kinetic energy

Answer 29

Ek = 1/2mv2

Question 30

Ek stands for what in kinetic energy?

Answer 30

Kinetic energy (J)

Question 31

m stands for what in kinetic energy?

Answer 31

mass of object (kg)

Question 32

v stands for what in kinetic energy?

Answer 32

Velocity/speed

Question 33

Define mechanical energy

Answer 33

Sum of the gravitational potential and kinetic energy at a point

Question 34

Mechanical energy

Answer 34

EM = Ep + Ek

Question 35

Define power

Answer 35

Rate at which work is done

Question 36

Symbol for power

Answer 36

P

Question 37

SI unit for power

Answer 37

watt (w)

Question 38

Formula for power

Answer 38

P = w/t

Question 39

If 1 joule of work is done in 1 second, how much power?

Answer 39

1 watt