home *** CD-ROM | disk | FTP | other *** search
- @In electric circuits the correct name for a 'battery' is:
- Cell
- Power supply
- Volts
-
- @What is the correct symbol for relay coil?
- #cir3
- Symbol 1
- Symbol 2
- Symbol 3
-
- @What is the correct symbol for a fixed resistor?
- #cir3
- Symbol 2
- Symbol 5
- Symbol 4
-
- @What is the correct symbol for a thermistor?
- #cir3
- Symbol 3
- Symbol 5
- Symbol 4
-
- @What is the correct symbol for a variable resistor?
- #cir3
- Symbol 4
- Symbol 2
- Symbol 3
-
- @What device do you use to measure the current in a circuit?
- Ammeter
- Voltmeter
- Ohm meter
-
- @If there is a gap in a wire in an electric circuit then:
- Nothing works
- It does not work as well
- It makes no difference to the way the circuit works
-
- @If a resistance is put into a circuit then the overall current flowing is:
- Reduced
- Just the same
- Increased
-
- @The positive connection on an Ammeter should be connected to:
- Positive on the cell
- Negative on the cell
- Both positive & negative on the cell
-
- @A switch turns the current in a circuit on and off because:
- It makes a gap in the circuit which stops the current
- It uses up the current
- It gets warm
-
- @Which of the symbols shown is a battery?
- #cir2
- Symbol 1
- Symbol 2
- Symbol 4
-
- @Which of the symbols shown is a switch?
- #cir1
- Symbol 2
- Symbol 1
- Symbol 4
-
- @Which one of the symbols shown is a diode?
- #cir2
- Symbol 4
- Symbol 2
- Symbol 3
-
- @Which one of the symbols shown is a thermistor?
- #cir2
- Symbol 3
- Symbol 1
- Symbol 2
-
- @What is the unit of resistance?
- Ohm
- Volt
- Ampere
-
- @40k Ohms can be written as:
- 40,000 Ohms
- 0.040 Ohms
- 400,000 Ohms
-
- @What device is used to measure the flow of current?
- Ammeter
- Voltmeter
- Thermocouple
-
- @In electric circuits what letter is used for current?
- I
- A
- p.d
-
- @6,500 Ohms can be written as:
- 6.5k Ohms
- 65k Ohms
- 0.65k Ohms
-
- @Potential difference is measured in:
- Volts
- Amps
- Ohms
-
- @Why are resistors placed in electrical circuits?
- To reduce the current flowing
- To increase the current flowing
- To produce heat
-
- @Two resistors, 470 and 1000 Ohms, are connected in series. Their combined resistance is:
- 1470 Ohms
- 470,000 Ohms
- 530 Ohms
-
- @What is a potentiometer used for?
- Varying the p.d in a circuit
- Reducing the current that flows
- Producing heat energy
-
- @Two resistors, 500 and 1000, are connected in series. The p.d across the 1000 ohm compared to the 500 ohm resistor will be:
- Double
- Half
- The same
-
- @A device that usually only allows current to flow in one direction is called a:
- Diode
- Rheostat
- Thermister
-
- @A diode contains which of the following?
- An anode and a cathode
- An anode only
- A base, collector and emitter
-
- @Some diodes have a 'heat sink' connected to them. This is to:
- get rid of excess heat
- increase the diodes p.d
- reduce the current flowing
-
- @A device whose restance changes with temperature is called a:
- Thermistor
- L.E.D
- L.D.R
-
- @A device whose resistance changes with light intensity is called a:
- L.D.R
- Transistor
- Rheostat
-
- @What does a diode do?
- Allows current to flow just one way through it
- Change its resistance with temperature
- Produce a sound when a p.d is applied to it
-
- @A reed switch is affected by:
- Magnetism
- Heat
- Light
-
- @In circuits, LED's are often wired in series with a resistor. Why?
- To protect them as they only need tiny currents
- To prolong the life of the resistor
- To make sure the effect on the circuit is minimal
-
-