# Electricity Flashcards Preview

## Edexcel iGCSE Physics > Electricity > Flashcards

Flashcards in Electricity Deck (16)
1
Q

What is the equation for electrical power?

A

P = I x V

2
Q

What is the equation for electrical energy?

A

E = P x t

3
Q

What is a fuse used for and how does it work?

A

Its a safety device. If the current is too high it melts the wire in the fuse and breaks the circuit.

4
Q

How does an Earth wire work?

A

If a live wire works loose and it comes into contact with the metal case of the appliance, the Earth wire prevents electrocution by carrying the current to the ground.

5
Q

How is static charge used in an inkjet printer?

A

The ink droplets are given a static charge which allows them to be directed to particular places on the paper by deflecting them between charged plates.

6
Q

How is static charge used in spray painting?

A

The tiny droplets of paint are given a static charge and the object to be painted (eg a car) is given the opposite charge. This causes the paint droplets to be attracted to the object.

7
Q

What are the advantages of using static charge in spray painting?

A

1) The amount of paint wasted is reduced

2) A more even finish is obtained

8
Q

What is the relationship between voltage, current and resistance?

A

V = I x R (voltage = current x resistance)

9
Q

Define current

A

The rate of flow of charge

10
Q

What device is used to measure potential difference?

A

Voltmeter

11
Q

What is a series circuit?

A

An electrical circuit with only one possible path for the flow of current

12
Q

What is a parallel circuit?

A

An electrical circuit with more than one possible path for the flow of current

13
Q

What device is used to measure current?

A

An ammeter

14
Q

What are the units of resistance?

A

Ohms

15
Q

What is a thermistor?

A

A resistor in which the size of the resistance is determined by it’s temperature.

16
Q

What is a non-Ohmic resistor?

A

A material in which voltage is not proportional to the current.