Physics Flashcards
What is the particle model of solids, liquids and gases?
Scientific theory that explains the properties of solids, liquids and gases. all matter is made of particles and that those particles behave differently in solids, liquids and gases.
Contrast heat and temperature
Heat deals with thermal energy, whereas temperature is more concerned with molecular kinetic energy.
What are the 3 methods of heat transfer?
- Conduction
- Convection
- Radiation
When does Conduction occur?
When 2 things at different temperatures touch each other and energy directly transfers from the material in the hotter object to the material in the colder object at the point of contact.
When does Convection occur?
When particles with a lot of heat energy in a liquid or gas move and take the place of particles with less heat energy.
When does Radiation occur?
Unstable atoms undergo radioactive decay, or they can be produced by machines. Radiation travels from its source in the form of energy waves or energised particles.
Explain convection currents using the particle model
As particles warm up (gain energy), they move farther apart, when it’s cold each section is a bit lighter. The material becomes less dense.
Explain the relationship between heat transfer methods and state (solid, liquid and gas)
In solids, heat passes from one point to another through conduction. In Liquids and gases, heat transfer takes place by convection.
How do conductors affect the conduction of heat?
Metals are especially good thermal conductors because they have freely moving electrons that can transfer thermal energy quickly and easily.
How does the material affect the transfer of heat by conduction?
The rate of energy transfer by conduction is higher when there is a large temperature difference between the substances that are in contact.
How does convection currents work using the particle model?
As particles warm up (gain energy), they move farther apart. Each section of the warmed material is left with fewer particles than when it was cold, so each section is a bit lighter.
Situations in which energy is transferred in form of waves?
Electromagnetic Waves
Describe sound waves
Wavelength (the length of one wave), amplitude (the height of a wave from equilibrium position to peak) and frequency, (the number of waves that pass a point in one second).
Recall that light is a form of energy that travels as an electromagnetic wave
Electromagnetic radiation
How does changes in frequency and amplitude of a sound wave affect the pitch and intensity?
The higher the frequency waves move back and forth in a regular rhythm, the higher the pitch of the sound we hear.
