EDEXCEL IGCSE

ELECTROMAGNETIC SPECTRUM

1. Calculate the speed of a water wave of wavelength 3m and frequency 6Hz.

2 Calculate the frequency of a wave in water of

Questions: Part A

1. (a) What is a wave? (b) Explain the difference between a transverse and longitudinal wave (see pages 91 and 92)

2. Define what is meant by (a) amplitude; (b) wavelength; (c) frequency and (d) time period. (see pages 92 and 93)

3. (a) State the wave equation. (b) Calculate the wavelength of a radio wave of frequency 10MHz, speed 300 000km/s.(see pages 93 and 94)

4. (a) What is wave diffraction? (b) Draw diagrams showing how diffraction is affected by the wavelength of a wave. (see page 97)

5. Calculate the frequency of a wave in water of wavelength 2.0m if its speed is 16m/s.

6. Calculate the speed of a water wave of wavelength 3m and frequency 6Hz.

7. Calculate the wavelength of a sound wave in water of frequency 300Hz if its speed is 1500m/s.

Visible light

Questions: Part B

1. Calculate the wavelength of a radio wave in of frequency 100 MHz if its speed is 300 000 000 m/s. 2. Calculate the frequency of a light wave of wavelength 0.000 7mm of speed 300 000 000 m/s. 3. The electromagnetic __________ is a group of waves that are divided into ________ bands. 4. Gamma rays have the ________ wavelength, highest frequency and ________. The rest of the spectrum, in order of increasing wavelength

are: 5. X-rays, _________, visible light, infra-red, ___________ and radio waves. 6. All electromagnetic waves travel at the same _______ through a __________, 300 000 000 m/s. 7. Give five common properties of all members of the electromagnetic spectrum. 8. List the colours of the visible spectrum in order of increasing wavelength 9. State the hazards of (a) microwaves; (b) ultra-violet; (c) X-rays and gamma rays.

Angle of incidence less than the critical angle: Refraction and PARTIAL reflection

1. Calculate the refractive index when light passes from air to glass if the angle of incidence is 30° and the angle of refraction 19º. 2. Calculate the angle of refraction when light passes from air to perspex if the angle of incidence is 50° and the refractive index, n = 1.50. 3. Calculate the angle of incidence when light passes from air to water if the angle of refraction is 20° and the refractive

d

1. Calculate the critical angle of glass to air if the refractive index of glass is 1.5

2. Calculate the critical angle of water to air if the refractive index of glass is 1.3

3 Calculate the maximum refractive index of a medium if light is to

Questions: Part C

1. Calculate the critical angle of glass to air if the refractive index of glass is 1.5 2. Calculate the refractive index when light passes from air to glass if the angle of incidence is 30° and the angle of refraction 19º.

3. Calculate the angle of refraction when light passes from air to perspex if the angle of incidence is 50° and the refractive index, n = 1.50.

4. Calculate the angle of incidence when light passes from air to water if the angle of refraction is 20° and the refractive index, n = 1.33.

5. Calculate the critical angle of water to air if the refractive index of glass is 1.3 6. Calculate the maximum refractive index of a medium if light is to escape from it into water (refractive index = 1.3) at all angles

below 30°. 7. Draw a diagram illustrating the law of reflection. 8. With the aid of a diagram explain how a plane mirror forms an image. also list the properties of this image. 9. (a) What is refraction? (b) Draw a labelled diagram showing how a light ray travels through a rectangular glass block. 10. (a) State the equation relating incident and refraction angles. (b) Calculate the angle of refraction with glass (n = 1.5) if the angle

of incidence is 55°. 11. (a) Explain what is meant by total internal reflection and critical angle. (b) state the equation for critical angle and calculate the

value of this angle for a substance of refractive index 1.4. 12. With the aid of diagrams explain how total internal reflection is used in (a) prismatic periscopes and (b) optical fibres. 13. (a) What is meant by dispersion? (b) How is it caused? (c) Draw a diagram (on colour) showing how a prism can disperse white

light.

Measuring frequency using an oscilloscope:

The time taken between peaks on an oscilloscope trace is equal to the time period, T of the sound wave.

Frequency = 1 / period f = 1 / T

Questions: Part D

1. The distance between peaks on an oscilloscope trace is 4cm. If the oscilloscope time scale is set at 1ms/cm calculate the frequency of the sound.

2. Sound is a ___________ wave that in air consists of a series of compressions and _____________. 3. Sound travels fastest through _______ but does not travel at all through a __________. 4. A ____________ sound wave is called an echo. Sound also undergoes ___________. 5. On average, humans can hear sound frequencies from __________ to ____________.