Building circuits
Make the following circuits and observe what you see. Use your
observations to circle the correct words to another the questions:
Series circuits - A series circuit is one where there are no branches.
The current can only follows one route.
1)Build circuit A. Observe how bright the light is. Now add another
cell to the circuit (Circuit B). What happens to the brightness of the
bulb?
When we add more cells to a circuit, the bulbs become
dimmer/brighter/do not change.
2) Now build circuit C and compare the brightness of the bulb to
that with the bulb in circuit A. How does adding more bulbs to a
circuit affect their brightness?
When we add more bulbs to a series circuit, the bulbs become brighter/do
not change/dimmer.
3) Now remove the bulb from circuit C leaving a gap in the circuit.
What happens to the other bulb?
When we remove a bulb from a circuit leaving a gap the other bulb
stays lit/won’t light/gets dimmer.
Parallel circuits- A parallel circuit is one where there are branches.
The current can follow more than one route.
Build parallel circuit D and observe the brightness of the bulb. Now
add another bulb in parallel (Circuit E).
4. What effect does adding another bulb have on the brightness of
the other bulbs?
Adding another bulb to a parallel circuit makes the other bulb
dimmer/brighter/stays the same brightness.
5. Now add another cell to circuit E to make circuit F. What effect
does adding another cell have on brightness of bulbs in a parallel
circuit?
When more cells are added to a parallel circuit, the bulb
becomes brighter/dimmer/stays the same brightness.
6. Remove a bulb from circuit F. What happens to the other
bulbs?
When a bulb is removed from a parallel circuit the rest stay on / turn off.
In a series circuit, adding more cells to a circuit makes
the bulbs brighter. Adding more bulbs to a series circuit
makes the bulbs dimmer. When we remove a bulb from a
series circuit the other bulb will no longer light.
In a parallel circuit, adding more cells makes the bulbs
brighter, adding more bulbs does not affect their
brightness. Removing a bulb from a parallel circuit does
not cause the other bulbs to turn off.
Uses of Series & Parallel Circuits