7.7 Parallel circuits

Question 1

What is a parallel circuit?

Answer 1

A circuit where individual components, or groups of omponents, are on thier own separate loop of the circuit.

Question 2

What is the advtantage of a parallel circuit

Answer 2

If one compoennt is removed/disconnected, it will hardly affect the other components

Question 3

How does the potential difference of each branch in a parallel circuit relate to the source p.d.

Answer 3

All branches in a parallal circuit have the same p.d. as the power supply

V (total) = V1 = V2 = …

So identical lamps connected in parallel will be as bright as a single lamp in the circuit

Question 4

How does current vary in the branches of a parallel circuit compared to the total currrent?

Answer 4

The total current in a circuit is equal to the total of all the currents through the separate branches

I (total) = I1 + I2 + …

Question 5

If you have two resistors in parallel, what is the total resistance?

Answer 5

It is LESS than the resistance of the smallest of the two resistors

Question 6

DIfference between series and parallel circuits: current

Answer 6

Series: current is the same through all components

Parallel: current depends on the resistance of each component

Question 7

DIfference between series and parallel circuits: potential difference

Answer 7

Series: total p.d. is shared across all components

Parallel: p.d. across each component is equal to the source p.d.

Question 8

DIfference between series and parallel circuits: resistance

Answer 8

Series: total resistance is the sum of all component resistances

Parallel: total resistance decreases as more components are added