Test-Electricity and Circuits

Question 1

What happens when two insulating materials are rubbed against each other?

Answer 1

They become electrically charged by friction. Electrons move from one to another. One is negatively charged and the other is equally positively charged.

Question 2

Why do you need to rub an object to make it attract another object?

Answer 2

It makes the object charged. Charged objects attract neutral objects.

Question 3

What happens when more bulbs are added to a parallel circuit?

Answer 3

Nothing. The bulbs stay the same brightness.

Question 4

Do two negative charges repel or attract?

Answer 4

Repel

Question 5

What type of circuit is used for home lighting?

Answer 5

A parallel circuit.

Question 6

What do you call an object what no total charge?

Answer 6

Neutral

Question 7

What do electrons carry in a circuit?

Answer 7

They carry energy from a cell to other components.

Question 8

What is the symbol for resistance called, and what does it look like?

Answer 8

Ω. It is called Ohms

Question 9

What is an electric current?

Answer 9

A flow of charged particles called electrons.

Question 10

Does a longer wire have more or less resistance than a shorter one?

Answer 10

More

Question 11

What is the formula for power?

Answer 11

Power=volts x current.

Question 12

What can a short circuit do to wires?

Answer 12

Make them overheat.

Question 13

I’m a series circuit us one bulb breaks, what happens to the rest of the circuit and why?

Answer 13

The bulbs go out. This is because the electrons can’t get through the bulb and give power to the next one.

Question 14

Equation for resistance?

Answer 14

Potential difference divided by current.

Question 15

What charge are electrons?

Answer 15

Negative

Question 16

What is the resistance of a bulb if it has a current of 10 A flowing through it when a potential difference of 240 Volts is out across it?

Answer 16

24 Ohms

Question 17

What provides yeh potential difference in a circuit?

Answer 17

The cell

Question 18

What has a higher resistance, insulators or conductors?

Answer 18

Insulators

Question 19

If a material has a current if 0.00025 A and 2.4 resistance, is it like let to be an insulator or conductor?

Answer 19

Insulator

Question 20

If a material has a potential difference if 2.4 and a current of 0.15, is it likely to be an insulator or a conductor?

Answer 20

Conductior

Question 21

What does a battery rating tell you?

Answer 21

The potential difference the battery will supply.

Question 22

What is the equation for a moment?

Answer 22

Moment = force x distance

Question 23

Name the advantages and disadvantages of low energy bulbs.

Answer 23

They are low energy consuming, but expensive and not very bright.

Question 24

What direction does the north seeking pole point towards when free to rotate?

Answer 24

The north (Scotland)

Question 25

What is the region around a magnet when it has magnetic effect called?

Answer 25

The magnetic field

Question 26

Name four magnetic materials

Answer 26

Iron steel cobalt and nickel

Question 27

Do like poles repel or attract?

Answer 27

Repel

Question 28

If I put two opposite poles next to eachother, what would happen?

Answer 28

They would attract

Question 29

What is a magnetic field?

Answer 29

A region of space where magnetic materials experience forces

Question 30

Name uses of magnets.

Answer 30

They are used in Compasses, fridges, speakers, microphones and computers

Question 31

Do magnetic field lines ever cross?

Answer 31

No

Question 32

The closer the lines are what happens to the magnetic dield?

Answer 32

They field is stronger

Question 33

What is the only way you can test if something is magnetic?

Answer 33

See if they repulse from another magnet.

Question 34

What is a permanent magnet?

Answer 34

A magnet that retains its magnetism

Question 35

What is a temporary magnet?

Answer 35

They loose their magnetism when the magnetic field disappears. Otherwise they act like a permanent magnet.

Question 36

What happens to the magnetism of an electromagnet as you add coils of wire?

Answer 36

The magnetism increases.

Question 37

How can you strengthen an electro magnet?

Answer 37

Increase the voltage, increase the number of coils or insert an iron core.

Question 38

What does passing a current through a wire do?

Answer 38

It creates a magnetic field around the wire.