Series Circuits

Question 1

What is the configuration of components in series circuits?

Answer 1

Components are connected in a line between the positive and negative of the power supply

Voltmeters are connected in parallel but do not count as part of the circuit.

Question 2

What happens if one component is removed or disconnected in a series circuit?

Answer 2

The circuit is broken and all components stop

This is generally not very handy, and very few devices are connected in series.

Question 3

How is the total potential difference (pd) distributed in a series circuit?

Answer 3

The total pd of the supply is shared between the components

V = V1 + V2 + …; the total pd always adds up to equal the source pd.

Question 4

What is true about the current in series circuits?

Answer 4

The same current flows through all components

I = I1 = I2 = …; the size of the current is determined by the total pd and total resistance.

Question 5

How do you calculate the total resistance in a series circuit?

Answer 5

Total resistance is the sum of individual resistances

R_total = R1 + R2.

Question 6

What effect does adding a resistor in series have on total current?

Answer 6

The total current in the circuit is reduced

This increases the total resistance of the circuit.

Question 7

What is the relationship between a component’s resistance and its share of the total potential difference?

Answer 7

The bigger a component’s resistance, the bigger its share of the total potential difference.

Question 8

Fill in the blank: In a series circuit, the current is the same everywhere, i.e., I = _______.

Answer 8

I1 = I2 = …

Question 9

What happens to the potential difference when more cells are connected in series?

Answer 9

There is a bigger pd when more cells are in series

For example, two cells with a pd of 1.5 V supply 3 V when connected in series.

Question 10

What is the formula for current in relation to voltage and resistance?

Answer 10

I = V / R

Question 11

If the total resistance of two resistors in series is 5Ω, what is the sum of their individual resistances?

Answer 11

5Ω

If R1 = 2Ω and R2 = 3Ω, then R_total = R1 + R2.

Question 12

True or False: In a series circuit, the potential difference across each resistor is equal.

Answer 12

False

The potential difference across each resistor is lower than the total pd shared among them.