Physics Chapter 6 - (Energy, Work And Power)

Define the term “Energy”.

The property of an object that can be stored and transferred.

Unit for “Energy”.

Joules (J).

Define the energy store “Energy System”.

When there are changes in energy, the energy is transferred. When there are no changes, the energy system is in equilibrium.

Define the energy store “Kinetic Energy”.

Moving objects that have energy in their kinetic store.

Define the energy store “Gravitational Energy”.

Objects that gain energy in their gravitational potential store when they are lifted through a gravitational field.

Define the energy store “Elastic Energy”.

Objects that have their energy stored in their elastic potential store if they are stretched, squashed or bent.

Define the energy store “Magnetic Energy”.

Magnetic materials interacting with each other have energy in their magnetic store.

Define the energy store “Electrostatic Energy”.

Objects that have charge such as electrons or protons that interact with one another have energy in their electrostatic store.

Define the energy store “Chemical Energy'“.

Chemical reactions transfer energy into or away from a substance’s chemical store.

Define the energy store “Nuclear Energy"“

Atomic nuclei release energy from their nuclear store during nuclear reactions.

Define the energy store “Thermal Energy”.

Objects that have energy in their thermal stores.

Define the transfer pathway “Mechanical Working”.

When a force acts on an object (e.g pushing or pulling).

Define the transfer pathway “Electrical Working”.

A charge moving through a potential difference (e.g current).

Define the transfer pathway “Heating (by particles)”.

Energy is transferred from a hotter object to a colder one (e.g conduction).

Define the transfer pathway “(Heating by) radiation”.

Energy transferred by electromagnetic waves (e.g visible light).

Formula for “Kinetic Energy”.

Eₖ = ½ mv².

Formula for “Gravitational Potential Energy”.

ΔE𝐩 = mΔgh.

What does the principle of conservation of energy state?

It states that energy cannot be created or destroyed. It can only be changed or transferred.

Define the term “Impulse”.

Changes of momentum within a period of time.

Formula for “Impulse”.

I = F x t.

Unit for “Impulse”.

Newton Seconds (Ns).