AQA-GCSE-Physics-P13 -Electromagnetic-Waves -Kerboodle -Answers

P13.1 The electromagnetic spectrum AQA GCSE Physics P13 Electromagnetic Waves Kerboodle Answers: Page No. 191​

1 a Wavelength of radio waves is greater than visible light waves. b All electromagnetic waves travel at a speed of 3.0 x 10sm/s (300 million m/s) through space or in a vacuum. c Frequency of X-ray is greater than frequency of infrared radiation. d Microwave to infrared region. 2 a Gamma rays > X-rays > infrared > radio.  b Microwave , Visible light and ultraviolet waves are missing from the list in a. 3 a The speed of electromagnetic waves in space = 3*108m/s Wavelength of radiowaves = 3*108/6*108 = 0.5m.  b Frequency of microwave = 3*108/0.30 = 109Hz. 4 Because they travels with same speed which is 3*108m/s.

P13.2 Light, infrared, microwaves, and radio wave sAQA GCSE Physics P13 Electromagnetic Waves Kerboodle Answers. Page No : 193​

1 a i Radiowaves. ii Visible light. b i Microwave. ii Radiowaves. 2 a Remote control handsets for TV and video equipment transmit signals carried by infrared radiation. When you press a button on the handset, it sends out a sequence of infrared pulses. Infrared radiation is used because suitable infrared pulses can easily be produced and detected electronically.   b  Radio waves of wavelengths from about 1 metre up to about 100m are used by local radio stations (and for the emergency services) because their range is limited to the area round the transmitter. 3  Wavelength = 3*108/24*108 = 0.125m. 4 a The microwaves bounce back and forth off the reflective metal wall.

P13.3 Communications AQA GCSE Physics P13 Electromagnetic Waves Kerboodle Answers Page No : 195​

1 a Light and infrared radiation. b  Optical fibres are more secure because the signals stay in the fibre. 2 a Because children have thinner skulls than adults, their brains might be more affected by mobile phone radiation. b  i Which carries a signal from transmitter to transmitter aerial. ii light waves has a much shorter wavelength than radio waves, and so can carry more pulses of waves so carry more information. 3  This is because microwaves can travel between satellites in space and the ground. Also, they spread out less than radio waves do, so the signal doesn’t weaken as much.
  • Radio waves of wavelengths less than about 1 metre are used for TV broadcasting from T\/ masts because they can carry more information than longer radio waves. So because of their longer wavelength and shortest frequency are used for terrestrial tv.
4 a Wavelength = 3*108/1.05*108 = 2.86m. b Radio waves of wavelengths greater than 100 mare used by national and international radio stations because they have a much longer range than shorter-wavelength radio waves.

P13.4 Ultraviolet waves X-rays, and gamma rays AQA GCSE Physics P13 Electromagnetic Waves Kerboodle Answers Page No : 197​

1 a X-rays are often used to detect internal cracks in metal objects. These kinds of application are usually possible because the more dense a substance is, the more X-rays it absorbs from an X-ray beam passing through it. b Yes. c There is a light-proof packet of photographic film inside the badge. The more radiation this absorbs, the darker it becomes when it is developed. To get an accurate measure of the dose received, the badge contains different materials that the radiation must penetrate to reach the film. These may include aluminium, copper, lead-tin alloy and plastic.  2 a Ultraviolet waves are harmful to human eyes and can cause blindness. UV wavelengths are smaller than visible light wavelengths. UV waves carry more energy than visible light waves.Ultraviolet waves are harmful to your skin. For example, too much UV directly from the Sun or from a sunbed can cause sunburn and skin cancer. It can also age the skin prematurely. If you stay outdoors in summer, use skin creams to block UV waves and prevent them reaching your skin. b i  By blocking incoming ultraviolet waves. ii Because too much UV directly from the Sun or from a sunbed can cause sunburn and skin cancer. It can also age the skin prematurely. If you stay outdoors in summer, use skin creams to block UV waves and prevent them reaching your skin. 3 a  Gamma radiation. b Barium. 4 a X-rays and gamma rays passing through substances can knock electrons out of atoms in the substance. The atoms become charged because they lose electrons. This process is called ionisation, and so X-rays and gamma rays are examples of ionising radiation. if ionisation happens to a living cell, it can damage or kill the cell.   b i X-ray. ii  Ultraviolet rays. P13.5 X-rays in medicine AQA GCSE Physics P13 Electromagnetic Waves Kerboodle Answers Page No : 199​ 1a  To obtain a radiograph of the stomach, the patient is given a barium meal before the X-ray machine is used . The barium compound is a good absorber of X-rays. b Doctors use X-ray therapy to destroy cancerous tumours in the body. 2 a X-rays pass through soft tissue, but they are absorbed by bones, teeth and metal objects that are not too thin. The parts of the film or the detector that the X-rays reach become darker than the other parts. So the bones appear lighter than the surrounding tissue, which appears dark .The radiograph shows a negative image of the bones. A hole oral cavity in a tooth shows up as a dark area in the bright image of the tooth.  b The film is light sensitive and if it wasn’t in a light proof cassette then the film would be surrounded by light so the picture that it takes would be ruined. c  X-rays are ionizing radiation and so can damage living tissue when they pass through it. High doses of radiation kill living cells. Low doses can cause gene mutation and cancerous growth. There is no evidence of a safe limit below which living cells would not be damaged. 3a  Doctors use X-ray therapy to destroy cancerous tumours in the body. b  The X-rays used for therapy carry much more energy than X-rays used for imaging. Low-energy X-rays are suitable for imaging because they are absorbed by bones and teeth but they pass through soft tissue and gaps such as cracks in bones. Low-energy X-rays do not carry enough energy to destroy cancerous tumours. The average radiation dose each person receives from ionising radiation is about 2 millisieverts per year. Medical X-rays account for about 13% of this.  a  Radiation dose is measured in sieverts (Sv) or millisieverts (mSv).High doses of radiation kill living cells. Low doses can cause gene mutation and cancerous growth b  Average radiation dose each person receives in one year  = 13/100*0.002 = 0.26millisieverts.

Summary questions AQA GCSE Physics P13 Electromagnetic Waves Kerboodle Answers Page No. 200​

1 a  D E A B C b i microwaves ii  gamma rays iii  infrared waves 2 a i  speed = wavelength × frequency ii  300 000 000 m/s2.9 m = 103 MHz b  amplitude gradually reduced as radio waves absorbed by air as they travel away from transmitter, at a certain distance, amplitude just large enough for radio signal to be detected, reducing power of transmitter reduces amplitude and so range is reduced 3 a mobile phone signals carried by microwaves which heat substances which absorb them so if too much microwave radiation, tissues in head (e.g. brain) may be damaged by heating effect b phone A emits less microwave energy per second so would not affect organs in head (e.g. brain/ear) as much c microwave radiation penetrates their thinner skulls more, also, smaller heads heat up more easily The figure shows an X-ray source that is used to direct X-rays at a broken leg. A photographic film in a lightproof wrapper is placed under the leg. When the film is developed, an image of the broken bone is observed. X-ray tube X-rays -film 4 a i  bone absorbs X-rays whereas surrounding tissue does not, X-rays pass through tissue and darken film when they reach it,  bones appear on film as lighter than surrounding area ii X-rays pass through fracture but not through bones so fracture appears darker than the bone b i barium absorbs X-rays so barium in stomach prevents X-rays reaching the X-ray film, image of stomach on X-ray appears lighter than area surrounding it, so easier to make a diagnosis ii  stomach movements would blur the image if the exposure time was as long as for a limb iii  X-rays ionise substances they pass through, exposure to ionising reduced by stopping low-energy X-rays reaching patient c ultrasound waves non-ionising, X-rays ionising and would harm baby 5 a process of creating ions, which are charged atoms or groups of atoms b X-rays, gamma rays c  can damage or kill living cells, cause cell mutation and cancerous growth 6 a When ultraviolet radiation is directed at invisible ink writing, UV radiation is absorbed by atoms in the ink which then emit visible light so the writing becomes visible b the further infrared radiation travels through air, the more it is absorbed by air molecules so a beam of infrared radiation would be too weak to detect after more than a few metres.

Practice questions AQA GCSE Physics P13 Electromagnetic Waves Kerboodle Answers Page No. 201​

01  01.1 infrared x-rays 01.2  longer lower the same energy 01.3 microwaves – used in mobile phones ultraviolet – used in sunbeds gamma – kills cancer cells 02 The following headline appeared in a local newspaper. Cound!!or Jones says that a!! mobile phone masts near local schools should be banned. They produce harmful radiation. 02.1 microwaves can penetrate the Earth’s atmosphere but radio waves are reflected 02.2 A  the mobile phone company may be biased 02.3 use a large sample size but did not include such factors as age/gender/lifestyle/amount of use of mobile phone so the conclusion is not valid 02.4 ionizing radiation can knock electrons out of atoms and this can kill living cells 03 Gamma radiation and X-rays are used in medicine. 03.1 gamma rays can kill the living cells of bacteria / gamma rays can pass through plastic because the air cannot get to the instruments they remain sterile 03.2 the gamma rays kill the cancerous cells in the tumour the rays are concentrated on the tumour the surrounding tissues only receive small doses of radiation 03.3 X-rays pass through soft tissue but are absorbed by bone 04 .1 opticians and other experts will make people aware of the dangers 04.2  wear sun hats and sunglasses cover skin with high factor sun cream 04.3  3.0 x 108 m/s  

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This page contains the detailed and easy notes for AQA GCSE Physics Waves for revision and understanding Waves.



AQA GCSE Paper 2: Complete Revision Summary

WAVES

  • Transverse and Longitudnal Waves
  • Properties of Waves
  • Reflection of Waves
  • Refractions of Waves
  • Sound Waves
  • Ultrasound
  • Electromagnetic Waves
  • Lenses
  • BlackBody Radiation





 

TRANSVERSE AND LONGITUDNAL WAVES

Waves are oscillations or disturbance that transfer energy from one point to another.

TRANSVERSE AND LONGITUDNAL WAVES

TRANSVERSE

LONGITUDNAL




PROPERTIES OF WAVES

Wave Speed

It is the distance travelled
by the wave each second.

Crest
It is the height of the
wave.

Amplitude

It is the maximum displacement
of the wave from the mean
position.

In the example it is 5 m

Frequency

It is the number of waves
passing each second.
It is measured in Hertz (Hz)

F = 1/T  1/4

=0.25H3

Wavelength

The distance between
two consecutive crests
or trough.

Time Period

The time it takes for one
wave to travel.

In the example, one wave
is completed in 4 second.

Trough
It is the depth of the wave.

WAVE SPEED




REFLECTION

  • It is the line perpendicular
    to the surface where reflection
    occurs.
  • It is the ray incident
    on the surface.
  • Angle of incidence is the
    angle between the incident
    ray and the normal.
  • It is the ray which is
    reflected from the surface.
  • Angle of reflection is the angle
    between the reflected ray and
    the normal.

Reflection is the phenomenon of bouncing
off the wave when it hits a medium.
eq: Reflection of light wave when it hits a plain
mirror.

LAWS OF REFLECTION

a) Incident ray, reflected ray
and normal are in the same
plane.

b) The angle of incidence
is equal to the angle
of reflection.

GCSE_Waves_Notes (1)

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IMAGE OF A PLANE MIRROR

  • It is a virtual image
  • Laterally Inverted
  • Upright
  • The same distance from the source.
REAL IMAGEVIRTUAL IMAGE
1. Image can be obtained on a screen.1. Image cannot be obtained on a screen
2. The rays actually meet where the image
is formed.		2. The rays happen to meet where
the image is formed.
eg Images of the cinema 

TYPES OF REFLECTION

REFRACTION

  • Bending of light as it travels from one medium to another.
  • Light bends because speed of light is different
    in different medium.
  • If the light is travelling from rarer to denser medium then
    it bends towards the normal. ∠r < ∠i
  • If the light is travelling from denser to rarer medium then
    it bends away from the normal.∠r > ∠i

The pencil appears to be
broken as the light is
refracted in water.

VISIBLE LIGHT

Visble light is a spectrum of 7 colours VIBGYOR

Each colour has its own freqency and wavelength.

The visible colour of the object will be the colour that is reflected by the object.

Opaque Object

Opaque objects
does not allow the
light to be transmitted
but absorb all
the light.

eg Book,

Translucent Object

These objects
allow some part
of the light to be
transmitted.

eg Plastic

Transparent Object

They allow the
light to be transmitted
through them
without any absorption

eq glass




SOUND WAVES

  • They are longitudnal Waves.
  • Sound does not travel through a medium.
  • Sound requires a medium to travel.
  • Sound wave is characterized by compression and
    rarefaction.
  • In sound waves, particles vibrate parallel
    to the direction of the wave.

The speed of the sound wave is 330m/s.

Human hearing range
20 Hz to 20,000 Hz

In Echo sounding, high frequency sound waves are sent to determine
the depth or find any object.

The time taken by the sound to come back is noted for the known speed
of sound.

S = vt/2

ULTRASOUND

It is the frequency of sound greater than 20,000 Hz.

ADVANTAGES

  • 1. They are non ionizing and
    harmless.
  • 2. They are partially reflected
    at the boundaries between
    different tissues, so they
    can scan even the soft tissues.

USES

1. Used in prenatal scanning.

2. Used to determine the depth of
the sea or the obstacle inside

3. Industrial Imaging .
4. Detecting flaws in metal castings.
water.




USES OF ULTRASOUND

ULTRASOUND SCANNER

Transducer sends ultrasound waves. It crosses
the body and reflected from the tissues. The Transducer
detects the waves reflected from the tissues and the
image is diplayed on the screen in the form of scans.

SONAR

  • Ultrasound waves are used to measure
    the depth of the sea or find the obstacle
    under water.
  • In SONAR, ultrasound is sent to determine
    the depth or find any object.
  • The time taken by the sound to come back is noted
    for the known speed
    of sound.

STRUCTURE OF THE EARTH

The crust and the upper mantle cracks and
forms the tectonic plate. The Tectonic
Plates causes Earthquake.

SEISMIC WAVES

  • Earthquake takes place
    when the rocks or the tectonic
    plates in the Earth’s Crust
    or the upper Mantle Moves
    due to forces inside the Earth.
  • Seismic Waves are the shock waves
    which originate when the forces inside
    the earth moves the rocks or
    the tecctonic plates. These waves travel
    through the Earth and also across its surface.
  • The Earthquake are detected by Seismometer.
  • The focus is the
    point from where
    the Earthquake
    originates.
  • Seismology is the study of
    Seismic Waves.
  • The nearest point on the surface of the
    focus is the epicenter.

SEISMIC WAVES

P-WaveS-Wave

·        They are longitudinal

·        They are faster than
other waves.

·        They can travel through
solids and liquids.

·        They can pass through
liquid outer core.

·        They are transverse

·        They are slower than other waves

·        They travel through
solids only

·        S-waves cannot pass
through the liquid
outercore.

  • Shadow Zones are the place
    where no P and S waves are detected.
  • S shadow zones where no S wave
    and only P waves are detected.

P and S Wave travel through the Mantle
changing directions with depth.

P waves refract at the boundary between mantle and outer core.

S waves being transfer do not travel through liquid outer core.

1. Liquid Outer core under the Mentle.

Shadow zones are detected as P waves refract twice.
Once while entering the core from the mantle
and leaving the core from the mantle. Since
the refraction is further away forming shadow
zones it suggests a liquid outer core under the mantle.

2. Solid Inner Core

Weak P waves in the shadow zones caused by the
refraction of P waves while crossing the boundary
between outer core and inner core.

Long (L-waves) travel the slowest.
They happen only in the Earth’s
crust and they cause more violent
movements.




ELECTROMAGNETIC SPECTRUM

  • It is the spectrum with all the
    electromagnetic waves arranged
    in the order of the increasing wavelength
    or frequency.
  • Electromagnetic waves are electric
    and magnetic disturbances that transfer
    energy (no matter)
    from one point to another.
  • All the electromagnetic waves travel
    with the speed of light-3 x10 8m/s
  • The frequency and the wavelength can
    be given by the formuale :- V = Fλ

ELECTROMAGNETIC SPECTRUM
MNEMONIC




GAMMA RAYS

SOURCE

Gamma rays are produced when
the radiactive substance emit
nuclear radiations.

PROPERTIES
  • They have the lowest wavelength.
  • They have highest frequency.
  • They travel with the speed of light.
USES

1. They are uses to disinfect food
and surgical equipment.

2. It is used to kill cancer cells. In
gamma treatment, the cobalt 60 is
used to direct the gamma radiation to
the cancer cells and kill it without
affecting the surrounding tissue.

DISADVANTAGES

1. Gamma Rays are highly ionizing.

2. Exposure to low dose of Gamma Rays can cause
gene mutation, DNA damage and even cancer.

3. Exposure to high dose of Gamma radiation
can caused killing of the cell.

X-RAYS

SOURCES

They are produced by stopping
high speed electrons.

PROPERTIES

1. They are electromagnetic wave which travels
with the speed of light.

2. They have wavelength greater
than Gamma Rays but smaller than
ultraviolet rays.

3. They have lower frequency than
Gamma Rays but greater than
ultraviolet rays.

4. Their wavelength is about the diameter
of the atom.

USES

1. Shorter wavelength X-rays are
used in X-ray therapy
to kill cancer cells without
destroying the healthy cells.

2. Longer wavelength X-rays are used
to photograph the internal structure
of the body.

DISADVANTAGES

1. X-Rays are highly ionizing
2. Exposure to a low dose of Gamma Rays can cause
gene mutation, DNA damage and even cancer.
3. Exposure to a high dose of Gamma radiation
can caused killing of the cell.

HOW X-RAYS WORK ?

  • X-rays are passed through the body.
  • The X-rays passes through the soft tissues but are
    absorbed by the bones and harder tissues.
  • The X-rays that pass through the softer areas reach
    the detector and appears to be black whereas the
    rays that are absorbed do not reach the detector
    and appears light in the image.
  • If any organs containing softer tissues needs to be
    photographed then patient is given a contrasting
    medium like Barium which becomes a good absorber
    of X-rays and helps the photography of that organ.
  • The detector contains the charged coupled device CCD
    which converts X-rays to light which then creates electronic
    signal which are used by the computer to make a digital
    image.

ULTRA VIOLET RAYS

SOURCE

1. They are produced from the Sun.
The Sun is the source of ultraviolet
rays.

PROPERTIES

1. They are electromagnetic wave which travels
with the speed of light.

2. They have wavelength greater
than X-Rays but smaller than
Violet light.

3. They have lower frequency than
X- Rays but greater than
violet light.

USES

They are uses as fluorescent markers
or fluorescent lamps which contains the
chemical which converts UV Light
to Visible Light.

DISADVANTAGES

1. They can cause sunburn and suntan

2. They can also lead to skin cancer.

3. They can also lead to blindness.

VISIBLE LIGHT

SOURCE

1. Sun and lamps emits light
2. It is the only part of the
specturm which is visible.

PROPERTIES

1. It is made up of 7 colours

2. VIOLET
INDIGO
BLUE
GREEN
YELLOW
ORANGE
RED
3. When the white light is passed
through the prism, it can give the
spectrum of colours.

USES
  • Light is used in a camera to take
    the picture.
  • Light is also used in Light Microscope
  • Light helps to see the object.
  • Light waves are also used in
    communication.
DISADVANTAGES

Too much exposure to visible light
can lead to cancer, blindness and
skin damage.

INFRA RED WAVES

SOURCE
  • All the hot objects like Kettle, Toaster,
    Radiator emits infrared radiation.
PROPERTIES

1. They are electromagnetic wave which
travels
with the speed of light.

2. They have wavelength greater
than visible light but smaller than
Microwaves.

3. They have a lower frequency than visible
light but greater than
microwaves.

USES

1. They are used in optical fibres
for communication.

2. They are used in remote
controls.

3. They are used as infrared
scanners to detect heat produced
by the body and unhealthy
tissues

4. Infrared cameras helps
to see objects in dark.

DISADVANTAGES

1. They can cause sunburn and suntan

2. They can also lead to skin cancer.

3. They can also lead to blindness.

MICROWAVES

 

The water in the food
absorb microwaves and
become heated and heats the
food preventing the microwave
from heating as it has no water.

SOURCE
  • They are emitted as Cosmic Microwave
    Background Radiation. Sun also emits
    some microwaves.
PROPERTIES

1. They are electromagnetic wave which
travels
with the speed of light.

2. They have wavelength greater
than infrared light but smaller than
Radiowaves.

3. They have a lower frequency than
infrared light but greater than
radiowaves.

4. They are found between Radiowaves
and Infrared Waves.

USES

1. They are used in communication.
2.They are used in satellite TV.
3. They are used in cooking.
4. They are used to carry mobile phone
signal.

DISADVANTAGES

1. Exposure to microwaves can heat
the body tissues.

2. Exposure to high dose of
microwaves can cause eye damage
and even cataract.




RADIOWAVES

SOURCE

Radio waves can be generated by natural sources
such as lightning or astronomical phenomena; or
by artificial sources such as broadcast radio
towers, cell phones, satellites and radar.

PROPERTIES

1. They are electromagnetic wave which
travels
with the speed of light.

2. They have the highest wavelength.

3. They have the lowest frequency.

USES
  • They are used in communication
    to carry TV, radio and mobile
    signals.
  • They are used in wireless connection
    and bluetooth connection.
DISADVANTAGES

1. Exposure to radiowave can heat
the body tissues.

2. Exposure to high dose of
radiowaves can cause eye damage
and even cataract.




LENSES

They are used to refract the light and forms the image of an
objects. They are used in camera.

CONVEX LENSCONCAVE LENS

1.   It is a converging lens

2. It is thicker at the center
than at the edges

3. It has a real focus

4. It converges a parallel
beam of light on refraction
through it

5. It is used in microscope,
magnifying glass

6. Used to correct short sight

1.   It is a diverging lens.

        2. It is thinner at the center
than at the edges.

3. It has a virtual focus

4. It diverges a parallel beam
of light on refraction
through it.

5. Used in some telescopes

6. Used to correct long sight.

CONCAVE LENS

mages formed is virtual, upright
and smaller than the object.

CONVEX LENS




KEY TERMS

  • Waves:- Waves are oscillations or disturbance that
    transfer energy from one point to another.
  • TRANSVERSE WAVES:- In transverse waves, the oscillations move
    perpendicular to the direction of the wave.
  • CRESTS :- It is the height of the wave.
  • AMPLITUDE :- It is the maximum displacement
    of the wave from the mean
    Position.
  • LONGITUDNAL WAVES :- In longitudnal waves, the oscillations move
    parallel to the direction of the wave.
  • FREQUENCY :- It is the number of waves
    passing each second.
    It is measured in Hertz (Hz)
  • WAVE SPEED:- It is the distance travelled
    by the wave each second.
  • TROUGH :- Trough
    It is the depth of the wave.
  • TIME PERIOD :- The time it takes for one
    wave to travel.
  • WAVELENGTH :- The distance between
    two consecutive crests
    or trough.
  • REFLECTION :- Reflection is the phenomenon of bouncing
    off the wave when it hits a medium.
    eq: Reflection of light wave when it hits a plain
    Mirror.
  • REFRACTION :- 1. Bending of light as it travels from one medium to
    another.

2. Reflection on a smooth surface.

3. Reflection on a rough surface.

  • OPAQUE :- Opaque objects
    does not allow the
    light to be transmitted
    but absorb all
    the light.
  • TRANSLUCENT :- These objects
    allow some part
    of the light to be
    transmitted.
  • TRANSPARENT :- They allow the
    light to be transmitted
    through them
    without any absorption.
  • ULTRASOUND:- It is the frequency of sound greater than 20,000
    Hz.
  • EARTHQUAKE:- Earthquake takes place
    when the rocks or the tectonic
    plates in the Earth’s Crust
    or the upper Mantle Moves
    due to forces inside the Earth.
  • SEISMOLOGY:- Seismology is the study of
    Seismic Waves.
  • SEISMIC WAVES:- Seismic Waves are the shock waves
    which originate when the forces inside
    the earth moves the rocks or
    the tecctonic plates. These waves travel
    through the Earth and also across its surface.
  • ELECTROMAGNETIC SPECTRUM:- It is the spectrum with all the
    electromagnetic waves arranged
    in the order of the increasing wavelength
    or frequency.
  • FOCUS:- Principle
    Focus or
    Focal points
    where the
    parallel rays
    meet or
    appears to meet.
  • LENS:- They are used to refract the light and forms the
    image of an
    objects. They are used in camera.
  • CONVEX LENS:- 1. It is a converging lens.
  • CONCAVE LENS:- 1. It is a diverging lens.
  • FOCAL LENGTH:- The distance between
    the focus and the
    center of the lens.




Disclaimer:

I have tried my level best to cover the maximum of your specification. But this is not the alternative to the textbook. You should cover the specification or the textbook thoroughly. This is the quick revision to help you cover the gist of everything. In case you spot any errors then do let us know and we will rectify it.

References:

BBC Bitesize

Wikipedia

Wikimedia Commons

Image Source:

Wikipedia

Wikimedia

Commons

Flickr

Pixabay

Make sure you have watched the above videos and are familiar with the key definations before trying these questions. It is also good to time yourself while doing these questions so that you can work on the speed as well.

P13- Electromagnetism