P1- Using Energy

Question 1

What is the Principle of Conservation of Energy?

Answer 1

The principle of conservation of energy applies to all energy changes, and states that energy cannot be created or destroyed, only transferred from one form to another.

This means that the total amount of energy is always the same.

Question 2

What is useful energy and what is wasted energy?

Answer 2

Useful energy is transferred to the place we want in the form we want it in.

Wasted energy is not useful.

Both useful and wasted energy is eventually transferred to the surroundings.

Question 3

What is efficiency and how is it calculated?

Answer 3

The efficiency of something tells us the fraction of the total energy that is useful.

Efficiency= (useful energy/ total energy) x 100

Energy transfer can be represented in a Sankey diagram.

Question 4

How can machines be made more efficient?

Answer 4

Machines can be made more efficient by:

• Reducing friction.
• Reducing air resistance.
• Reducing electrical resistance.
• Reducing noise due to vibrations.

Question 5

What are the 5 types of energy in action and 3 types of stored potential energy?

Answer 5

In action:

1. Light.
2. Sound.
3. Kinetic.
4. Nuclear.
5. Electrical.

Potential:

1. Chemical.
2. Elastic.
3. Gravitational.

Question 6

What does a transducer do?

Answer 6

A transducer is an object that changes one type of energy to another type.