Three 1.5 V cells are connected in series so that they give out a p.d. of 4.5 V. One of the cells is then reversed. The new p.d. is:

1.   ?    0 V
2.   ?    1.5 V
3.   ?    3.0 V
4.   ?    4.5 V

Which one of these is not necessary for a circuit?

1.   ?    Circuit is complete.
2.   ?    A source of voltage.
3.   ?    A switch
4.   ?    Circuit is made of conducting materials

Which one of these correctly describes a conventional current?

1.   ?    Current regarded as flowing from positive to negative.
2.   ?    Electrons regarded as flowing from positive to negative.
3.   ?    Current regarded as flowing from negative to positive.
4.   ?    Electrons regarded as flowing from Negative to positive.

Resistance is measured in:

1.   ?    amps
2.   ?    volts
3.   ?    coulombs
4.   ?    ohms

Resistance =

1.   ?    current × voltage
2.   ?    current ÷ voltage
3.   ?    voltage ÷ current
4.   ?    voltage + current

The current and voltage are measured in a filament lamp glowing at normal brightness. The resistance is worked out. Then the resistance is checked with an ohm meter, and this is found to be less than half the worked out value. The correct reason for this is:

1.   ?    The Ohm meter is faulty.
2.   ?    The voltmeter is faulty
3.   ?    The calculation from the voltage can current was done incorrectly.
4.   ?    The filament of the lamp gets hot, and the resistance goes up.

Which one of these best describes the action of a normal diode?

1.   ?    When forward biased, the diode conducts at + 30 V. It does not allow a current to flow when reverse biased.
2.   ?    When forward biased, the diode conducts at + 0.6 V. It does not allow a current to flow when reverse biased.
3.   ?    When reverse biased, the diode conducts at + 0.6 V. It does not allow a current to flow when forward biased.
4.   ?    It does not conduct at all.

Which one of these statements describes the action of a light dependant resistor?

1.   ?    The resistance increases as the light level increases.
2.   ?    The LDR gives off light when it is forward biased
3.   ?    The LDR generates electricity as the light level increases
4.   ?    The resistance decreases as the light level increases.

Which one of these components would be used as a sensor for an electronic thermometer?

1.   ?    LED
2.   ?    Thermistor
3.   ?    LDR
4.   ?    Diode

Which one of these is NOT correct for a series circuit?

1.   ?    The voltage add up to the battery voltage.
2.   ?    The resistances add up to a total resistance.
3.   ?    The currents add up to a total current.
4.   ?    The current is the same all the way round the circuit.