Science - Chapter 13: Electricity

What is electricity?

A form of energy and can be converted into other types of energy​

Where is electricity produced from in Brunei Darussalam?

Natural gas which is used to power turbines and generators​

What must occur for an electrical appliance to work?

Electrical charge must flow through it

What is current?

Movement of electrical charge

What is electrical current carried by?

Electrons (negative charge)

What is a circuit?

The path that current flows through

What is the symbol for current?

I

What is the S.I Unit of current?

Ampere (A)

What is used to measure current?

Ammeter

How do electrons flow within the circuit?

From negative terminal to positive terminal of a dry cell

What is voltage?

The energy that makes electric charges move

What is used to measure voltage?

Voltmeter

What is the S.I unit of voltage?

Volt (V)

How is an electric circuit formed?

When all the electrical components are connected in a loop

What is an open circuit?

Switch is off and no current is flowing

What is a closed circuit?

Switch is on and allow current to flow

open switch

closed switch

light bulb

cell

battery

voltmeter

resistor

variable resistor

ammeter

What is a series circuit?

There is one pathway for current to flow.

What is a parallel circuit?

More than one pathway for current to flow

How must an ammeter be connected?

Ammeter must be connected in series

How should the ammeter be connected to the dry cell?

The positive terminal of the ammeter must be connected to the positive terminal of the battery. In addition, the negative terminal of the ammeter must be connected to the negative terminal of the battery

How is current measured in a series circuit?

Total Current = I1 = I2 =…

How is current measured in parallel circuit?

Total Current = I1 + I2 +…

How is voltage measured in series circuit?

Total Voltage = V1 + V2…

How is voltage measured in parallel circuit?

Total Voltage = V1 = V2…

What is resistance?

Resistance opposes the flow of the current

What is resistance measured by>

Resistors

What are the 2 types of resistors?

Fixed resistor

Variable resistor (Rheostat)

What is the difference between a fixed resistor and a rheostat?

The resistance does not change in a fixed resistor, but the resistance can be changed in a rheostat.

How do you calculate resistance in a series circuit?

Total Resistance = R1 + R2 +…

How do you calculate resistance in a parallel circuit?

1/Rt = 1/R1 +1/R2 +…

What is a two-way switch?

2 switches controlling the same component

What is a fuse?

Component that allows only certain current to flow.

What is the importance of a fuse?

Preventing damage to electrical appliance when there is large current flowing.

What are fuse ratings?

1A, 3A, 5A, 13A, 15A and 30A

What are the 3 wires found in a three-pin plug?

• Live

• Neutral

• Earth (Metal casing)

What is the old color of a live wire?

Red

What is the old color of a neutral wire?

Black

What is the old color of an earth wire?

Green

What is the new color of a live wire?

Brown

What is the new color of a neutral wire?

Blue

What is the new color of an earth wire?

Green and yellow

What is the importance of the earthing wire?

Preventing electric shock

How does the earth wire prevent electric shock?

Connect earth wire to the metal casing of electrical appliances and carry current to the ground instead of the person touching the appliances.