1. Parallel Circuits & Current
D. Crowley, 2008

2. Parallel Circuits & Current
Saturday, February 23, 2019
Parallel Circuits & Current
To know how adding more bulbs to a parallel circuit affects the brightness of bulbs

3. Parallel Circuit Look at the following circuit+ -
branch 1
branch 2
How will the current differ between branch 1 and branch 2?

4. Parallel Circuit
The current (no. of electrons) which go through each branch depend on the resistance of the component + -
branch 1
branch 2
E.g. if branch 1 has a high resistance, then not many electrons will pass through it, and instead more will pass through branch 2

5. Football Stadium
Think about the circuit like a football stadium (turnstiles are like the resistance of the branches, and the fans are the electrons)
If one turnstile is very slow (a high resistance) then more fans will go to another turnstile which may be quicker (lower resistance) + -
This is like branch 1 – a high resistance causes the electrons to get around the circuit via an easier route (branch 2)
branch 1
branch 2

6. Parallel Circuits
In a parallel circuit, if a lamp or component breaks the components on the other branches keep working
Unlike a series circuit, the lamps stay bright if you add more lamps in parallel

7. Experiment

8. Experiment

9. Parallel Circuits
The current which passes through each component depends on its resistance (the lower the resistance, the bigger the current which flows through)
The total current flowing around the circuit is equal to the total of all the currents through the separate branches

10. Electricity Crossword
Complete the electricity crossword
Across: -
Cell
Circuit
Fuse
Nerves
Metal
Switch
Series
Down: -
Current
Conductor
Parallel
Resistance
Ammeter
Amps