7j: Electrical Circuits

We measure electrical current with
1. an ammeter
2. a voltmeter
3. an Ampmeter
4. a compass
Electrical current is measured in
1. Amperes
2. Volts
3. Ohms
4. gallons
Electrical current is a flow of
1. electrons, which are negatively charged
2. electrons, which are positively charged
3. neutrons, which have no charge
4. protons, which are positively charged
Low energy light bulbs
1. are more efficient than ordinary light bulbs
2. give out less light than ordinary light bulbs
3. generate more heat than ordinary light bulbs
4. are less efficient than ordinary light bulbs
If a switch is "closed", it
1. is switched on
2. is switched off
3. cannot be operated without a key
4. is protected by insulating covers
In a series circuit
1. if one bulb fails, the others stop working
2. if one bulb fails, the others keep working
3. the bulbs are brighter than in a parallel circuit
4. the bulbs all have the same voltage across them
In a parallel circuit
1. if one bulb fails, the others keep working
2. if one bulb fails, the others stop working
3. the bulbs are dimmer than in a series circuit
4. the bulbs all must have the same current through them
An electrical fuse
1. protects against fires and overloads
2. protects against electric shocks
3. melts if the voltage is too high
4. disconnects the neutral wire if there is a fault
The flex colours in a plug are
1. live-brown, neutral-blue, earth-green/yellow
2. live-red, neutral-black, earth-green/yellow
3. earth-brown, neutral-blue, live-red
4. live-blue, neutral-brown, earth-green/yellow
The wires in a plug are called
1. live, neutral, earth
2. live, neutral, negative
3. positive, neutral, earth
4. positive, negative, earth
An electromagnet is stronger with
1. an iron core
2. an air core
3. an aluminium core
4. a copper core
Power is measured in
1. watts
2. joules
3. decibels
4. volts
a light bulb transfers
1. electrical energy to heat + light
2. light to electrical energy
3. volts to light
4. voltage to heat
voltage is measured in
1. Volts
2. Amps
3. Amperes
4. Watts
a battery is
1. several cells connected together
2. another name for an electrical cell
3. never rechargeable
4. a store of electrical energy
stored inside an electrical cell, there is
1. chemical energy
2. electrical energy
3. heat energy
4. light energy
an incandescent lamp
1. has a thin piece of wire that gets hot when a current flows through it
2. is extremely efficient
3. means a "low energy" bulb
4. means a "fluorescent" lamp
in a parallel circuit
1. the current is "shared out" between the "arms" of the circuit
2. the current is the same through all components in the circuit
3. the voltage is "shared out" between the "arms" of the circuit
4. the current is the same all the way round
in a series circuit
1. the current is the same all the way round
2. the current is "shared out" between the "arms" of the circuit
3. the voltage is the same across all the components
4. the power of all the components is the same
the fuse in a plug is to
1. break the circuit if too much current flows
2. keep the current at 13 Amps
3. prevent the current from becoming too small
4. prevent the voltage from becoming too large
which of these would need a 13A fuse?
1. an electric heater
2. a bedside lamp
3. a TV set
4. a computer printer
which of these would need a 3A fuse?
1. a bedside lamp
2. an electric heater
3. a microwave oven
4. an electric cooker
a bimetallic strip
1. bends when the temperature changes
2. conducts heat badly
3. does not conduct electricity
4. is a "sandwich" of three different metals
a sensor
1. is an input device
2. is an output device
3. powers a circuit
4. is controlled by a circuit
an actuator
1. is an output device
2. is an input device
3. powers a circuit
4. controls a circuit
an electrical insulator
1. is a very bad conductor
2. is a very good conductor
3. is a good conductor
4. allows current to flow
an electrical conductor
1. allows current to flow
2. does not allow current to flow
3. does not have free electrons to carry a current
4. does not include most metals
a defibrillator
1. is used in hospitals to restart a patient's heart
2. is a type of heart pacemaker
3. is a sensing device
4. is used to measure the current in a circuit
a rheostat
1. is a name for a variable resistor
2. senses temperature
3. is a type of lamp
4. measures current
for a current to flow, there must be
1. a complete circuit
2. a closed switch
3. an open switch
4. a d.c. power supply