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1.      Alice connects four light bulbs for her model house, as shown.  She puts the bulbs into the holes in the back wall.

(a)     When Alice turns the switch on, the bulbs do not light up.  The batteries are not flat.  None of the bulbs is broken.
Why do the bulbs not light up?

(b)     Alice makes the circuit work.  When she turns the switch on, the bulbs are not very bright.
What must Alice add to the circuit to make the bulbs brighter?

(c)     The four bulbs in the circuit are the same.  Which statement is correct?

The diagrams show two ways to write the model house.

                                               circuit 1                                                       circuit 

(d)     (i)      In circuit 1, bulb B breaks and goes out.
What happens to the other bulbs in this circuit?

1 mark

(ii)     In circuit 2, bulb C breaks and goes out.
What happens to the other bulbs in this circuit?

1 mark

2.      The diagram shows a circuit for controlling an electric motor. This circuit can make the motor turn forwards or backwards.  

Complete the table to show which lamp, if any, is lit and in which direction, if any, the motor turns.  

The first row has been done for you

switch A

switch B Which lamp, if any, is lit? In which way, if any, does the motor turn?
up down lamp 1 forwards
up up
down up
down down

4 marks

 

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