Series & Parallel Circuits Using Filament Lamps

This practical lesson covers:

  1. How to set up series and parallel circuits.
  2. The effect of varying the number of components in series / parallel

Investigating series and parallel circuits using bulbs


Aim:

To construct electrical circuits to test series and parallel circuits using resistors.

Background information:

When resistors are connected in series, the total resistance increases, and the current through each component is the same. Conversely, in a parallel configuration, the total resistance decreases, and the voltage across each resistor remains constant.

In this practical, you will explore the effects of these configurations on circuit current and voltage.

Variables:

  1. Independent variable - Number of resistors added in series / parallel  
  2. Dependent variable - Circuit current and voltage
  3. Control variables - D.C power supply, value of each resistor

As the resistors are added in series, the overall circuit resistance..

stays the same

increases

decreases

0

/

1

As the resistors are added in parallel, the overall circuit resistance...

decreases

increases

stays the same

0

/

1

How could the student calculate the overall circuit resistance?

circuit resistance = power supply voltage × circuit current
circuit resistance =power supply voltage circuit current​
circuit resistance =circuit current power supply voltage​

0

/

1

As more resistors are added in series, the voltage across each one will..

increase

stay the same

it is impossible to tell based on the information provided

decrease

0

/

1

As more resistors are added in parallel, the voltage across each one will...

increase

decrease

it is impossible to tell based on the information provided

stay the same

0

/

1