Electromagnetic Waves (Edexcel GCSE Physics)

Draw one line from each use of wave to the matching electromagnetic wave.

One line has been drawn for you.

Ultraviolet light has a higher frequency than infrared light.

Which of these colours of visible light has the highest frequency?

Figure 1 shows how the brightness of a source of light changes with wavelength.

Figure 1

Describe how the brightness changes with wavelength.

Figure 7 shows a tuning fork.

Figure 7

When the prongs of the tuning fork are struck, the prongs vibrate in the directions shown by the arrows on Figure 7.

Describe how the vibrating tuning fork causes a sound wave to travel through the air.

You may add to the diagram if it helps your answer.

The following descriptions describe waves from different parts of the electromagnetic spectrum.

Complete each description by adding the name of the wave.

Use the name of each wave only once. Each description refers to a different part of the electromagnetic spectrum.

Description 1

used in cooking

used in short-range communication

typical wavelength 900 nm

name of wave ..................................................

Description 2

used in cooking

used in communication

typical wavelength 150 mm

name of wave ...............................................

Description 3

used in communication

produced by oscillations in electrical circuits

typical wavelength 150 m

name of wave .............................................

Description 4

used in medical scanning

is emitted by the nucleus of an atom

typical wavelength 2.0 × 10⁻³ nm

name of wave ..............................................

Higher Tier Only

When white light crosses the boundary between air and glass, it can split up into the colours of the spectrum.

Explain, in terms of speed, why the light behaves like this.

Visible light travels at a speed of 3.00 × 10⁸ m/s in a vacuum.

State the speed with which gamma radiation travels through space.

Table 1 shows an incomplete list of the electromagnetic spectrum.

Table 1

(i) Complete Table 1 by filling in the missing EM waves.

[3]

(ii) Suggest what the arrow is indicating.

[1]

Higher Tier Only

Figure 1 shows an X-ray of a broken bone. 

Figure 1

Describe the interaction between the X-rays and  

(i) soft tissue.

[1]

(ii) bone.

[1]

X-rays are dangerous to work with because they have a high frequency and transfer large amounts of energy. 

People who work with X-rays need to take precautions to keep themselves safe. 

Suggest one way that workers can keep themselves safe when working with X-rays.

Figure 1 shows a radio wave. Each 1 cm square is equal to 2 m.

Figure 1

(i) State the wavelength of the radio wave in Figure 1.

[1]

(ii) On Figure 1, sketch a wave that has a greater amplitude and lower frequency.

[2]

A radio wave with a frequency of 20 GHz travels through the vacuum of space.

Calculate the wavelength of this radio wave.

The speed of light in a vacuum is 3.00 × 10⁸ m/s

 wavelength = .................................... m

Give two useful applications of radio waves.

Explain why radio waves are safe for humans to use.

Which list shows electromagnetic radiation in order of decreasing wavelength?

Which of the following statements about infrared radiation is correct?

State which region of the electromagnetic spectrum is used in each situation. 

(i) Security marking on banknotes.

[1]

(ii) Motion sensors.

[1]

(iii) Fibre optic communications.

[1]

An optical fibre is inserted into a patient's body to examine the liver during keyhole surgery.

Explain why visible light is more useful and safer than X-rays during this surgery.