P4 Electricity- Physics Paper 1

Question 1

What is the mass in kg of a proton?

Answer 1

1.67 X 10^-27

Question 2

What is the mass in kg of a neutron?

Answer 2

1.67 X 10^-27

Question 3

What is the mass in kg of an electron?

Answer 3

9.11 X 10^-31

Question 4

What is the relative mass of a proton?

Answer 4

1

Question 5

What is the relative mass of a neutron?

Answer 5

1

Question 6

What is the relative mass of an electron?

Answer 6

1/2000

Question 7

What charge does an atom become if an electron is lost?

Answer 7

Positive

Question 8

What charge does an atom become if an electron is gained?

Answer 8

Negative

Question 9

Why can’t insulators conduct electricity ?

Answer 9

Because they don’t have de-localised electrons

Question 10

What moves through electrical conductors?

Answer 10

A current, which is a flow of moving electrons

Question 11

What sort of force is static electricity?

Answer 11

A non-contact force

Question 12

What is static electricity?

Answer 12

Electric charge that accumulates on an insulated object, for example because of friction.

Question 13

What happens when insulating materials rub against each other?

Answer 13

they may become electrically charged. Electrons, which are negatively charged, may be ‘rubbed off’ one material and on to the other. The material that gains electrons becomes negatively charged. The material that loses electrons is left with a positive charge. And, so the 2 materials are attracted to each other

Question 14

What happens when a polystyrene rod is rubbed with a duster ?

Answer 14

the friction causes electrons to gain energy. Electrons gain enough energy to leave the atom and ‘rub off’ onto the polythene rod.

Question 15

What’s the new charge of the polystyrene rod?

Answer 15

Negative, as it’s gained electrons

Question 16

What’s the charge of the duster ?

Answer 16

Positive, as it’s lost electrons

Question 17

Insulators prevent…

Answer 17

electrons from moving and the charge remains static

Question 18

Conductors…

Answer 18

hold a charge, as electrons can move through them

Question 19

What force will a charged object feel from another charged object?

Answer 19

A non contact force, which will result in either attraction or repulsion

Question 20

What do all charged objects have around them?

Answer 20

An electric field, which shows how they’ll react with other charged particles

Question 21

What does an electric field exert?

Answer 21

A force on other charged objects

Question 22

What is a Van de Graaff generator?

Answer 22

A machine that causes friction between a rubber belt and plastic rollers in order to build up electrical charge on a metal dome. The van de graaf generator removes electrons to produce a positive charge.

Question 23

What happens to a person touching the dome of a Van de Graaff generator?

Answer 23

they will lose electrons and become positively charged. The same will happen to each of their hairs. Since the person, their head, and each of the hair follicles are all positively charged, the hairs will repel from the head and from every other strand causing them to stick out from the head in all directions.

Question 24

What are electric fields usually represented as?

Answer 24

Diagrams with arrows

Question 25

What does the direction of the arrow show ?

Answer 25

the way a positive charge will be pushed.

Question 26

What does the closeness of the arrows show?

Answer 26

The closer together the arrows are, the stronger the field and the greater the force experienced by charges in that field. This means that the field is stronger closer to the object.

Question 27

With a positive electric field, the arrows point…

Answer 27

outwards

Question 28

With a negative electric field, the arrows point..

Answer 28

inwards

Question 29

What is the field between 2 parallel plates ( one positive, one negative) called?

Answer 29

A uniform field. The field lines would be straight, parallel and point from positive to negative

Question 30

What happens if an electric field is strong enough?

Answer 30

charges can be forced though insulators such as air and a spark will occur.

Question 31

What is friction?

Answer 31

A force that opposes or prevents movement and converts kinetic energy into heat.

Question 32

What is a radial field?

Answer 32

When field lines spread out from a single point.

Question 33

Air is an insulator. But, what happens when it gets ionised?

Answer 33

It’s much more conductive and a charge can flow through it.. this is known as a spark

Question 34

What causes sparking to happen?

Answer 34

As an electric charge builds up on an object, the potential difference between the object and the earth increases. If the potential difference is large enough, electrons can jump across the gap between the charged object and the earth , which causes a spark .