Physics

What is thermal energy?

A measure of the vibration of particles in a substance.

What does measuring an object's thermal energy indicate?

You are measuring its total kinetic energy from all its particles.

What is an insulator?

A material or device that stops or slows down the flow of electricity, heat, or sound.

How do insulators work?

They work by not allowing charged particles to flow.

What is a conductor?

A material that allows electric charge or current to flow through it easily since they have a low resistance.

How does a conductor work?

They work by having atoms that have free outer electrons that are loosly bound. Once voltage or electric field is applied, the electrons break free and move from atom to atom.

What is gravitational potential energy?

The stored energy an object gains due to its height above the ground

What is kinetic energy?

Energy an object has due to its movement.

What is electrical energy?

Energy that forms due to build up or flow of electrons

What is weight?

The downward force due to an objects mass and acceleration due to gravity

What is convection?

Heat transfer by moving fluid particles

How does convection work?

It works by fluid being heated which leads particles to gain energy and move faster, leading them to spread apart and decrease in desity. Low density fluid (warm) rises. Colder, denser fluid sinks. This forms a convection current.

What substance does convection work best?

It can only work with fluids because particles need to flow.

What is conduction?

Heat transfer by direct contact

How does conduction work?

When particles in an object are near to a heat source they will vibrate quicker, causing them to collide with neighbouring cold particles and giving them thermal energy. This makes the whole object hot. Metals conduct well since they have free electrons + tightly packed atoms. Plastic, wood, ceramic=insulators

What substance does conduction work best?

Best in solid since particles are super tight, weak in liquid, very weak in gas

What is radiation?

Heat transfer by electromagnetic waves

How does radiation work?

Heated objects emit infrared radiation since particles have high thermal energy which they give off to other objects that absorb it and warm up. Dark, mate surafces absorb/emit best, light, shiny surfaces less so

What substance does radiation work best?

Since no particles are needed, it works on liquids, solids, gases, and vaccum.

What are the two types of latent heat?

Fusion= solid → liquid

What is latent heat?

The amount of energy required to turn 1kg of a substance from one state to another

What is work?

The transfer (or transformation) of energy that causes an object to move or change shape

What is power?

The rate at which work is done

What is current?

The rate at which electric charge flows past a point in a circuit

What is voltage?

The difference in electric potential energy between to pointsin a circuit. It acts as the pressure that pushes electrical charges through a circuit

What is resistance?

The measure of a components hindrance to the flow of charge

What is specific heat capcity?

The amount of energy required to heat 1kg of a substance by 1°C. It is also the amount of energy that substance will release when it cools by 1°C. The lower the heat capcity, the less energy required to change the temperature of a substance.

What is energy transfer?

Moving energy from one object to another without changing forms

What is energy transformation?

When energy changes from one form to another

What happens to current when another bulb is added in series?

Current decreases because resistance increases, making it hard for current to flow

What happens to voltage when another bulb is added in series?

The voltage is now shared across all bulbs so bulbs will become dimmer

What happens to resistance when another bulb is added in series?

Resistance goes up since the total resistance is the sum of their individual resistances

What happens to current when another bulb is added in parallel?

Current increases because adding a new branch gives it an extra path to flow through

What happens to resistance when another bulb is added in parallel?

Resistance decreases because adding a new branch gives it an extra path to flow through

What happens to voltage when another bulb is added in parallel?

Voltage stays the same since all paths are independent

Definition of temperature

The average kinetic energy of particles in a substance