Physics Flashcards
Draw the circuit symbols
Go draw them
What is a V-I graph and what do they look like?
- V-I graphs show how the current varies as you change the potential difference
Different fixed resistors:
- a directly proportional graph
Filament Lamp:
- as the temp of filament lamp increases, resistance increases
- a curve
What happens to resistance as temperature increases?
- resistance increases
Describe the potential difference, current and resistance in a series circuit
Potential difference:
- total PD is shared between various components
- PD around circuit add up to equal PD across the battery
Current:
- Same everywhere
Resistance:
- total resistance is sum of individual resistance
Describe the potential difference, current and resistance in a parallel circuit
- PD is same across all components V1=V2=V3
- Current is shared between branches
Where is the ammeter?
- always connected in series
Where is the voltmeter?
- always connection in parallel with a componenet
What is an alpha particle
two neutrons and two protons
- helium nucleus same
- they are strongly ionising because they are big, heavy and slow moving
What is a beta particle
- move quite fast and quite small (they are electrons)
- penetrate moderately
What is gamma ray
- can penetrate far
- weakly ionising because they pass through
- no mass no charge
What blocks alpha beta and gamma
- alpha: paper
- beta: thin aluminium
- gamma: thick lead
What happens during alpha decay
nucleus loses two protons and two neutrons
- atomic numbers goes down by 2 and atomic mass goes downy 4
What happens during beta decay
- neutron splits into a proton and electron
- atomic number goes up by one but mass number remains unchanged
When light passes into an optically denser medium, what happens to the light and vice versa
- slows down
- light refracts towards the normal
