Electricity and Electromagnetism

Question 1

What is an Electric Current?

Answer 1

The flow of charge around a circuit

Question 2

What does The Potential Difference do?

Answer 2

It pushes the Current around

Question 3

What happens if you increase the potential difference

Answer 3

More current will flow

Question 4

Do all batteries have the same potential Difference?

Answer 4

No

Question 5

What is Resistance

Answer 5

It is how easily Electricity Can Flow

Question 6

What components can have Resistance in a Circuit?

Answer 6

Resistance is anything in a circuit that slows down the flow of current

Question 7

What is Resistance measured in

Answer 7

Ohms

Question 8

How can you find out the Resistance?

Answer 8

By doing

Resistance =

Potential Difference divide by current

Question 9

Batteries provide the driving force to push charge around a circuit

What is this driving force called?

Answer 9

Potential Difference

Question 10

What is the only way of telling if an object is charged?

Answer 10

to see if it repels another charged object.

Question 11

What does it mean by “in series”?

Answer 11

Connected to a circuit in such a way that the same current flows through each component in turn.

Question 12

When two components are connected in series,______________________

Answer 12

you can follow the path through both components without lifting your finger or going back over the path you have already taken.

Question 13

How can you find out if an object is a conductor or an insulator?

Answer 13

You set up a series circuit with a cell, lamp and wires. Leave a gap in the circuit between two of the wires. Then connect the two wires using pieces of each material and see if the lamp lights up

Question 14

Examples of Conductors

Answer 14

Metal Elements
Graphite
Mixtures of metals
Salt Solution

Liquid Calcium Chloride

Question 15

Examples of Insulators

Answer 15

Most Non mental elements

Diamond
Plastic
Wood
Rock

Question 16

What 3 things do you need to know when drawing magnetic field diagrams?

Answer 16

each field line has an arrowhead on it

the field lines come out of the north pole and go into the south pole

the field lines are more concentrated at the poles

Question 17

What is an Electromagnet?

Answer 17

An electromagnet is a type of magnet in which the magnetic field is produced by an electric current

Question 18

How can Electromagnet be turned off?

Answer 18

Unlike Bar magnets, Electromagnets can reverse the direction of current (turn the battery around)

Question 19

What is the DC Effect?

Answer 19

When you put a length of wire in a magnetic field and pass a DC current through it (such as from a battery), the wire will move.

Question 20

To make a simple DC motor, you need:

Answer 20

two bar magnets
a coil of wire wrapped around something to support it
an axle for the coil of wire to spin around
two half rings (‘split rings’)

Question 21

How does coil rotation happen?

Answer 21

the coil of wire has an electrical current running through it because it is connected to the cell this generates a magnetic field around the wire the current
is turned on and off at the correct time so the magnetic field of the wire interacts with that of the two magnets this makes the coil rotate

Question 22

How does A DC motor work?

Answer 22

The two bar magnets are held so that the north pole of one magnet faces the south pole of the other magnet.
The coil of wire is mounted in the gap between the two magnets. The split rings make electrical contact with the coil and reverse the current every half turn.
When an electric current flows through the coil, a force is exerted on the coil, causing it to spin.

Question 23

Dp

Answer 23

Electrons move from the Duster to the polythene rod

Question 24

Ad

Answer 24

Electrons move from the Acetate rod to the Duster

Question 25

What is a magnetic field?

Answer 25

A region where magnetic materials experience a force

Question 26

How can u find the magnetic field lines using iron fillings

Answer 26

The iron fillings will align along the field lines

Question 27

What is the only way of telling if an object is charged? Justify your answer

Answer 27

To see if it repels another charged object as a charged object can attract uncharged insulators eg pieces of paper