P4 - Electric Circuits - Complete

Question 1

What are the subatomic particles of the atom?

Answer 1

A proton, a neutron and an electron

Question 2

What is a charged atom called?

Answer 2

An ion

Question 3

What charge would an electron being removed result in in a otherwise neutral atom?

Answer 3

+1

Question 4

Why do some insulators become charged when you rub them with another insulator?

Answer 4

As some of the electrons are charged from one material to the other

Question 5

What charge would rubbing a polythene rod and a dry cloth together result in?

Answer 5

Negative

Question 6

What charge would rubbing a perspex rod and a dry cloth together result in?

Answer 6

Positive

Question 7

Like charges ……….. Unlike charges …………..

Answer 7

Repel, attract

Question 8

The force between two charged objects is a ………………….. force

Answer 8

Non-contact

Question 9

What is the function of a (chemical) cell?

Answer 9

To push electrons around a complete circuit. A battery is two or more cells put together

Question 10

What is the function of a switch?

Answer 10

A switch enables the current in a circuit to be switched on or off

Question 11

What is the function of an indicator?

Answer 11

An indicator, such as a bulb, is designed to emit light when current passes through it

Question 12

What is the function of a diode?

Answer 12

It lets current pass in one direction only

Question 13

What is the function of an ammeter?

Answer 13

An ammeter measures the current within a circuit

Question 14

What is the function of a fixed resistor?

Answer 14

A fixed resistor limits the current in a circuit

Question 15

What is the function of a variable resistor?

Answer 15

A variable resistor allows the current to be varied

Question 16

What is the function of a fuse?

Answer 16

A fuse is designed to melt and therefore ‘break’ the circuit if the current is greater than a certain amount

Question 17

What is the function of a heater?

Answer 17

A heater is used to transfer electric current into heat that can heat the surroundings

Question 18

What is the function of a voltmeter?

Answer 18

A voltemeter is used to measure potential difference

Question 19

What is an electric current?

Answer 19

The flow of charge

Question 20

What is the size of an electric current also called?

Answer 20

The rate of flow of charge

Question 21

What is electric charge measured in?

Answer 21

Coulombs (C)

Question 22

What is electric current measured in?

Answer 22

Amperes (A)

Question 23

What is 1 Amp equal to in Coulombs?

Answer 23

1 C per second

Question 24

What is the equation that links charge flow and time taken?

Answer 24

Charge flow, C = Current, A x Time taken, t

Question 25

What is potential difference?

Answer 25

The amount of work done on an electric component per coulomb of charge that passes through that component

Question 26

How is a voltmeter connected to a circuit?

Answer 26

In parallel to the component it is measuring

Question 27

What is the equation that links potential difference and energy transferred?

Answer 27

Potential difference across a component, V = Energy transferred, J / Charge, C

Question 28

What causes resistance within a circuit?

Answer 28

Since the electrons have to push through many vibrating metal ions in the filament and wires - causing resistance

Question 29

What is the equation that links resistance and current?

Answer 29

Resistance, Ohms (Omega symbol) = Potential difference, V / Current, A

Question 30

What is Ohm's law?

Answer 30

The current through a resistor at constant temperature is directly proportional to the potential difference across the resistor

Question 31

What happens to the resistance of a filament lamp as its temperature increases?

Answer 31

Its resistance increases

Question 32

What happens to a thermistor's resistance as its temperature increases?

Answer 32

Its resistance decreases

Question 33

What happens to a light dependent resistor's resistance if light intensity increases?

Answer 33

Its resistance decreases

Question 34

In a series circuit, ____________________ current passes through every component

Answer 34

In a series circuit, the same amount of current passes through every component

Question 35

In a series circuit, the total potential difference of the power supply is _____________________ components

Answer 35

In a series circuit, the total potential difference of the power supply is shared between components

Question 36

The total potential difference of cells in series is the sum of ____________________________

Answer 36

The total potential difference of cells in series is the sum of the potential difference of each cell

Question 37

The total current in a parallel circuit is the sum of the ______________________________

Answer 37

The total current in a parallel circuit is the sum of the currents through the separate branches

Question 38

In two parallel branches, how is this current split?

Answer 38

Equally - down the middle

Question 39

For components in parallel, the potential difference across each component is ____________

Answer 39

For components in parallel, the potential difference across each component is the same

Question 40

What is the equation that links current, voltage and potential difference?

Answer 40

Current (A) = Potential Difference (V) / Resistance (Ohms, Omega symbol)

Question 41

What effect on the total resistance does adding more in parallel resistors have?

Answer 41

The total resistance goes down