# Physics P3

• Created by: abbiedye
• Created on: 29-07-18 10:44

## What is Internal Energy?

• The amount of kinetic energy and potential energy of all the particles in the system
• A rise in temperature - particles speed up - gain kinetic energy
• Melts or boils - energy breaks bonds - increases potential energy
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## What is Specific Heat Capacity?

• The amount of energy needed to raise the temperature of 1kg of a substance by 1 degrees

change in thermal energy = mass x specific heat capacity x temperature change

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## What are the states of matter?

SOLID

• strong forces of attraction
• held together in regular patterns
• not much energy - can only vibrate

LIQUID

• weaker forces of attraction
• close together - can move past each other
• some energy - random directions - low speeds

GAS

• no forces of attraction
• more energy - free to move
• random directions and speeds
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## How is force created and increased?

• When particles collide, they exert a force called pressure
• In a sealed container - outward gas pressure = total force exerted by all the particles
• Increasing the temperature - energy transferred to kinetic energy stores - more collisions
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## How do you calculate density?

• Density = measure of the 'compactness' of a substance

density = mass / volume

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## What is Internal Energy?

• Internal energy is the energy stored by the particles that make up a system
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## What are the changes of state?

• Solid to Liquid = melting
• Liquid to Solid = freezing
• Liquid to Gas = boiling / evaporating
• Gas to Liquid = condensing
• Solid to Gas = sublimating
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## What is Specific Latent Heat?

• The amount of energy needed to change 1kg of a substance from one state to another without changing its temperature

energy = mass x specific latent heat

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