Paper 1

Question 1

Equation for acceleration

Answer 1

acceleration = change in velocity / time taken

Question 2

What is friction

Answer 2

A force that opposes motion

Question 3

What is terminal velocity

Answer 3

The object moves at a steady speed in a constant direction because the resultant force acting on it is zero

1) object accelerates because it has weight
2) as speed increases so does drag
3) the forces balance and terminal velocity is reached

Question 4

practical: investigate how extension varies with applied force for helical springs, metal wires and rubber bands

Answer 4

The spring constant of a spring can be found by carrying out an experiment.

The unloaded length of a spring is measured.

Slotted masses are added to the spring.

Record each stretching force in N and the corresponding length of the spring.

The extension is the new length minus the unloaded length.

Question 5

Hookes law

Answer 5

Gradient of a force-extension graph is associated with Hooke’s law
(Spring constant)

Question 6

Current in a resistor in domestic products

Answer 6

Resistance causes transfer of electrical energy to heat energy. Some components are designed to have a high resistance to make sure this happens, for example electrical heaters

Question 7

Relationship between power, current and voltage

Answer 7

P = IV

Question 8

A.C. and D.C.

Answer 8

Mains electricity is alternating current (oscillating voltage/current)
Direct current is supplied by a cell or battery (constant voltage/current)

Question 9

Current in a series circuit

Answer 9

Is constant

Depends on the applied voltage

Question 10

Graphs for resistors metal filament lamps and diodes

Answer 10

-

Question 11

Voltage, current and resistance relationship

Answer 11

V = IR

Question 12

If you increase resistance, the current

Answer 12

Decreases

For example adding more components

Question 13

that light is part of a continuous electromagnetic spectrum that includes (in order)

Answer 13

radio, microwave, infrared, visible, ultraviolet, x-ray and gamma ray radiations

Question 14

Wavelength and frequency in electromagnetic spectrum

Answer 14

decreasing wavelength and increasing frequency

Question 15

Uses of radio waves

Answer 15

broadcasting and communications

Question 16

Uses of microwaves

Answer 16

Cooking and satellite transmission

Question 17

Uses of infrared radiation

Answer 17

Heaters and night vision equipment

Question 18

Uses of visible light

Answer 18

Optical fibres and photography

Question 19

Uses of ultraviolet light

Answer 19

Fluorescent lamps

Question 20

Uses of x rays

Answer 20

observing the internal structure of objects and materials, including for medical applications

Question 21

Excessive exposure of microwaves

Answer 21

Internal heating of body tissue

Question 22

Excessive exposure of infrared

Answer 22

Skin burns

Question 23

Excessive exposure of ultraviolet

Answer 23

Damage to surface cells and blindness

Question 24

Excessive exposure of gamma rays

Answer 24

Cancer, mutation

Question 25

What are light waves

Answer 25

Transverse waves that can be reflected and refracted

Question 26

Law of reflection

Answer 26

the angle of incidence equals the angle of reflection

Question 27

How do optical fibres work

Answer 27

Optical fibres made of plastic or glass consist of a central core surrounded by a cladding with a lower refractive index Light signals passing through the core always hit the boundary at angles higher than c so the light is always totally internally reflected This transmits information along them

Question 28

What do optical fibres do

Answer 28

They are being used increasingly for telephone and broadband internet cables Also for medical purposes to be able to see inside the body

Question 29

What is a critical angle

Answer 29

when the angle of incidence is equal to the critical angle, the angle of refraction is 90 degrees

Question 30

relationship between critical angle and refractive index

Answer 30

sin c = 1 / n

Question 31

Principle of conservation of energy

Answer 31

It is not possible to create or destroy energy.

Question 32

relationship between efficiency, useful energy output and total energy output:

Answer 32

efficiency = useful energy output / total energy output x 100

Question 33

relationship between density, mass and volume

Answer 33

volume = mass / density

Question 34

relationship between pressure, force and area

Answer 34

pressure = force / area

Question 35

Molecules in a gas

Answer 35

have random motion and that they exert a force and | hence a pressure on the walls of a container

Question 36

the Kelvin temperature of a gas is proportional to

Answer 36

average kinetic energy of its molecules

Question 37

why does a nail exert more pressure on wood than on a hammer

Answer 37

- pressure is force divided by area - the forces on wood and hammer are equal - smaller area of nail is in contact with wood

Question 38

Why is pressure inversely proportional to volume

Answer 38

As volume increase the space between the particles increases therefore frequency of collision decreases. Average force felt by container decreases so pressure decreases

Question 39

Pressure and Kelvin temperature at constant volume.

Answer 39

As you heat the gas, the kinetic energy of the particles increases, and thus so does their average speed. This means more collisions per second with the walls, and they exert a larger force on the wall. This causes in the total pressure being exerted by the particles to rise

Question 40

What is a magnetic field line

Answer 40

Magnets exert forces without touching

Question 41

How to produce a uniform magnetic field

Answer 41

A uniform magnetic field is comprised of straight, parallel lines which are evenly spaced. Between two opposite charges on bar magnets, a uniform magnetic field is formed

Question 42

Comet orbits

Answer 42

Around the sun | Highly elliptical

Question 43

Planet orbits

Answer 43

Around the sun | Slightly elliptical

Question 44

Moon orbits

Answer 44

Around planets | Circular

Question 45

Uses of gamma rays

Answer 45

sterilising food and medical equipment.

Question 46

energy transfers

Answer 46

mechanically, electrically, by heating, by radiation