Paper 2

Question 1

Unit of measurement for weight (force)

Answer 1

Newtons

Question 2

What equipment can you use to measure weight

Answer 2

Newtonmeter / spring balance

Question 3

How do you calculate weight

Answer 3

Weight = mass x gravitational field strength (10)

Question 4

What is acceleration

Answer 4

How quickly velocity is changing

Question 5

What is a moment

Answer 5

A turning effect of a force

Question 6

What is the principle of moments

Answer 6

If an object is balanced then: Total Anticlockwise Moments = Total Clockwise Moments

Question 7

How do you calculate a moment

Answer 7

Moment = Force x Perpendicular distance between pivot and force

Question 8

What is the unit of measurement for moments

Answer 8

Newton meters (Nm)

Question 9

How to calculate momentum

Answer 9

Momentum = mass x velocity / P=mv

Question 10

Definition of conservation of momentum

Answer 10

When no external forces act

Question 11

What is Hooke’s law

Answer 11

Extension is proportional to force

Question 12

Describe an experiment for Hooke’s law

Answer 12

Set up spring on clamp on a weighted stand
Record initial length
Add a series of equal weights one after another and record each time.
Plot a graph using the results (x axis - extension, y axis - weight)

Question 13

What happens to the graph line when the force becomes great enough

Answer 13

It curves

Question 14

What is the limit of proportionality

Answer 14

The maximum force where force is proportionate to extension

Question 15

What is a static charge

Answer 15

A charge that builds up in one place and is not free to move

Question 16

Why is static charge more common in insulators

Answer 16

The current cant move

Question 17

Common electrical conductors

Answer 17

Copper and silver

Question 18

Common electrical insulators

Answer 18

Plastic and rubber

Question 19

How are positive and negative electrostatic charges produced on materials

Answer 19

Electrons are scraped off one material, which becomes positive, and dumped on the other, which becomes negative

Question 20

Give an example of friction in insulating materials

Answer 20

Polythene rod rubbed with duster, electrons move from duster to rod. Rod becomes negatively charged, and duster has equal positive charge

Question 21

Explain electrostatic phenomena in terms of movement of electrons

Answer 21

An electric charge builds up on an isolated object (e.g. jumper), voltage between object and earth increases.
If voltage gets too high, electrons jump across gap between charged object and the earth, this is the spark.

Question 22

Snell’s law equation

Answer 22

Refractive index = Sin I / Sin R

Question 23

Equation for kinetic energy

Answer 23

KE = 1/2MV^2

Question 24

Describe the magnetic field around a straight wire

Answer 24

Made of concentric circles with the wire in the centre

Question 25

Describe the magnetic field around a flat circular coil

Answer 25

Concentric elipses around each magnetic coil with a straight line in the middle

Question 26

Descrive the structure of a transformer

Answer 26

Two coils (primary and secondary) joined with an iron core

Question 27

What effect do the transformers have on alternating voltage and why

Answer 27

They change the voltage of a current depending on the amout of turns on each coil

Question 28

What are step up transformers

Answer 28

Increase the voltage, as they have more turns in the secondary coil than the primary coil

Question 29

What are step down transformers

Answer 29

Decreases the voltage, as they have more turns in the primary coild than the secondary coil

Question 30

Use of step up transformers in energy transmission

Answer 30

The lower the voltage the higher the current, because Power = Voltage x Current, current causes wires to heat up therefore more voltage is needed to prevent wires heating up.

Question 31

Use of step down transformers in energy transmission

Answer 31

Used at the end of transmission to reduce the voltage to it's safer and more useful for places like homes.

Question 32

Transformer equation

Answer 32

Primary Voltage / Secondary Voltage = Primary turns / Secondary turns

Question 33

Equation for orbital speed

Answer 33

2 x Pi x orbital radius (m) / time period (s)

Question 34

What is a redshift

Answer 34

an observed increase in the wavelength or decrease in the frequency of the light from light sources that is moving away from the earth the light shifts towards the red section of the visible part of the electromagnetic spectrum

Question 35

How do you calculate the amount that light from a galaxy is redshifted

Answer 35

Change in wavelength / Reference wavelength = Velocity of galaxy / Speed of light

Question 36

How does redshift suggest that the universe is expanding

Answer 36

Further away galaxies have greater redshifts than nearer ones, which means that distant galaxies are moving faster away from us than nearer ones, therefore the universe is expanding.

Question 37

Describe what happens to frequency and wavelength if a wave source is moving relative to an observer

Answer 37

It's the same wave pattern but at lower frequencies and longer wavelengths.

Question 38

What is a solenoid

Answer 38

A coil of wire