Module 3.3 - Work, Energy And Power

Question 1

Define work done/energy transferred

Answer 1

The product of the force and the distance moved by the force in the direction of movement

Question 2

Define closed system

Answer 2

Any system in which all the energy transfers are accounted for
Energy or matter cannot enter or leave

Question 3

What is the Principle of the Conservation of Energy?

Answer 3

The total energy of a closed system remains constant

Energy cannot be created or destroyed, only transferred fro. One form to another

Question 4

What are the factors that affect how much gravitational potential energy an object has?

Answer 4

Its vertical height above the ground
Its mass
The value of the gravitational field strength at that point

Question 5

What is GPE’s relationship to the three factors that affect it?

Answer 5

Directly proportional

Question 6

What are the factors that affect an object’s kinetic energy?

Answer 6

Mass

Velocity

Question 7

What is KE’s relationship to the two factors that affect it?

Answer 7

Directly proportional to mass

Directly proportional to the square of the velocity

Question 8

Define power

Answer 8

The rate of work done/at which energy is transferred from one form to another

Question 9

What does the total amount of energy transferred depend on?

Answer 9

Power rating

Length of time for which it is used

Question 10

Define efficiency

Answer 10

The ratio of useful output energy to total input energy