Electricity

Question 1

What do ammeters connect in?

Answer 1

Series circuit

Question 2

As resistance increases, what happens to the current?

Answer 2

Current decreases.

More resistance = less current

Question 3

What is a formula used to calculate

Voltage, current, resistance?

Answer 3

Voltage = Current × Resistance

V=IR

Question 4

What happens to the current if the voltage is increased?

Answer 4

As the voltage is increased, the current also increases.

Question 5

If the voltage increases, what happens to the resistance of a resistor?

Answer 5

As the voltage increases, the resistance of the resistor stays the same. (For a resistor).

Question 6

Alternating current (A.C.)

Answer 6

The flow of charge constantly changes direction back and forth.

Example - mains electricity

Question 7

Direct current (D.C.)

Answer 7

The flow of charge is always in the same direction.

Example - battery

Question 8

What is the function of a FUSE?

Answer 8

The fuse melts if a fault develops an the current becomes too high.
The fuse protects the flex from overheating.

Question 9

Series circuit rules

Answer 9

• the current us the same at all points.

- the voltage across the resistors adds up to the voltage supply.

Question 10

Current in parallel circuit rule

Answer 10

Currents in the branches add up to the total current.

Question 11

Voltage in a parallel circuit rules

Answer 11

• currents in the branches add up to the total current.
• voltages are all the same.

(Opposite of the rules for series)

Question 12

Why are lamps connected in parallel?

Answer 12

So that:

• all lamps have the same voltage across them.
• the lamps c

Question 13

Example of A.C.

Answer 13

Mains electricity

Question 14

Example of D.C.

Answer 14

Battery

Question 15

What happens to resistors in series?

Answer 15

Resistors in series add up.

Question 16

What happens to resistors in parallel?

Answer 16

1/RT = 1/R1 + 1/R2 + 1/R3

Question 17

Charge formula

Answer 17

Q = It

Q = charge in coulombs (C)
I = current (A)
t = time (secs)

Question 18

Electric current

Answer 18

Electric current is the rate of flow of electric charge, it is the quantity of charge that passes a point every second.

Current is measured in amps.
1 amp = 1 coulomb per second.

Question 19

Types of charge

Answer 19

+ and -

Question 20

What is electricity in current?

Answer 20

Electricity is the flow of charged particles.

An electric current is the flow of electrons around a circuit.

Question 21

What is charge measured in?

Answer 21

Coulombs (C)

Question 22

What does charge mean?

Answer 22

1 ampere of current means 1 coulomb of charge passes a point every second.

1 ampere of current = 1 coulomb per second
1A = 1Cs‐¹

Question 23

Draw oscilloscope traces for A.C. & D.C. voltages

Answer 23

Draw for practice

D.C. (straight line)

A.C (waved line)

Question 24

What are all charged objects associated with?

Answer 24

An electric field around them.

Question 25

Electric field force

Answer 25

An electric field exerts a force on another charged particle placed into the electric field.

Question 26

Pathway of charged particles in an electric field: Between 2 oppositely charged particle plated

Answer 26

The charged particle will be attracted to its the oppositelly charged plate and move towards it. It will be repelled form the same type of charged plated and move away.

Question 27

What is potential difference/ voltage?

Answer 27

Potential difference (voltage) is the energy given to each coulomb of charge that flows around a circuit. P.d. / voltage is a measure of the energy given to charges in a circuit.

Question 28

p.d./ voltage across a component

Answer 28

p.d. / voltage across a component causes a current to flow through the component.

Question 29

What is resistance?

Answer 29

Resistance is a measure of opposition to current (as resistance increases, current decreases).

Question 30

What type of energy does a resistor change electrical energy into?

Answer 30

A resistor changes electrical energy into HEAT energy.

Question 31

Describe an experiment to describe ohms law

Answer 31

Draw: Include: variable power supply, resistor, ammeter( in series), voltmeter (in parallel)

Question 32

Formula for voltage, current & resistance

Answer 32

V = IR ``` V = voltage (V) I = amperes (A) R = resistance (♤) ```

Question 33

Ohms law for a resistor on a graph

Answer 33

Can be shown as a diagonal straight line. This means that the resistance of the resistor stays the same as voltage and current both increase.

Question 34

Calculatong resistance of a resistor from a voltage, current graph

Answer 34

Can be calculated from the gradient of the best fit straight line

Question 35

Voltage, current graph for a metal filament lamp

Answer 35

Curves upwards showing that the lamps resistance increases as its temperature increases.

Question 36

What is the power rating of an appliance?

Answer 36

The power rating of an appliance is the amount of energy used per second. ?

Question 37

Common fuses

Answer 37

1A, 3A, 5A, 13A

Question 38

Charged particles in an electric field

Answer 38

Charged particles have an electric field around them. A charged particles will experience a force in an electric field. This is what causes charged particles to be attracted or repelled when near each other.

Question 39

Pathway of charged particles in an electric field: Near a single point charge

Answer 39

It will move towards the point charge if opposite charge and away if the same charge.

Question 40

Pathway of charged particles in an electric field: Between to oppositely charged points

Answer 40

It will move away (be repelled) from luke charge and move towards (be attracted) to opposite charge.

Question 41

Pathway of charged particles in an electric field: Between two like charged points

Answer 41

The forces will likely be balanced and the particle will not move towards each other. (It will move in s straight line because it will be equally attracted to both points)

Question 42

Temperature and resistance of a conductor.

Answer 42

As the temperature of a conductor increases its resistance also increases.