Topic Summaries
Types of resistors
Energy and power
Renewable energy and efficiency
Charge, current, and electric fields
Potential difference and resistors
Electricity
Volume and gases
States of matter and heat capacity
Radiation
Nuclear fusion and fission
Forces
Velocity and acceleration
Gravity and Newton's Laws
Moments and elastic potential
Stopping, braking, and momentum
Properties of waves
Electromagnetic waves
Refraction and lenses
Light, colour, and ray diagrams
Absorbing and emitting infrared radiation
Magnetic fields
Motor effect, generator effect, and transformers
Science skills: Experimental procedures
Science skills: Presenting and using data
Science skills: Measuring results
Energy and power
Renewable energy and efficiency
Charge, current, and electric fields
Potential difference and resistors
Electricity
Volume and gases
States of matter and heat capacity
Radiation
Nuclear fusion and fission
Forces
Velocity and acceleration
Gravity and Newton's Laws
Moments and elastic potential
Stopping, braking, and momentum
Properties of waves
Electromagnetic waves
Refraction and lenses
Light, colour, and ray diagrams
Absorbing and emitting infrared radiation
Magnetic fields
Motor effect, generator effect, and transformers
Science skills: Experimental procedures
Science skills: Presenting and using data
Science skills: Measuring results
- An ohmic conductor is one that has constant resistance. This means the current through the conductor is proportional to the potential difference across it.
- Most wires and standard resistors behave as ohmic conductors, so long as their temperatures are kept constant.
- Variable resistors are ohmic conductors that can have the value of their resistance manually changed.
- The resistance of a filament lamp increases as the current through it increases. This is because the current is causing the filament in the lamp to heat up.
- A diode is a component that only allows current to flow in a single direction.
- This is because its resistance is extremely high if the potential difference across it is below +0.7 V.
- An LED is a diode that emits light when a current flows through it.
- The resistance of a thermistor decreases as its temperature increases. They can be used in circuits that react to temperature changes, such as thermostats.
- The resistance of an LDR decreases as the light intensity upon it increases. They can be used in circuits that react to changes in brightness in the surroundings, such as automatic lights.
Unlock Types of resistors
Subscribe to SnapRevise+ to get immediate access to the rest of this resource.
Premium accounts get immediate access to this resource.