Module 2 - Waves

Module 2 - Waves

1. What is a transverse wave?

   • The vibration of the particles in the medium is perpendicular to the direction of the wave propagation.
   • Some examples are:
   • (1) Water waves
   • (2)EM waves
   • (3)Waves on a string

2. What is a longitudinal wave?

   • The vibrations of the particles in the medium is parallel to the direction of wave propagation.
   • Some Examples:
   • (1)Sound

3. What is amplitude?

   • The maximum displacement of a particle from its equilibrium position.

4. What is frequency?

   • The number of cycles/oscillations/vibrations of a particle in a wave per second or the number of complete waves passing a point per second
   • Measured in Hertz - SI Base unit m-1

5. What is time period?

   • Time taken for one complete oscillation.

6. What is wavelength?

   • The distance between two successive crests or troughs or the distance travelled by the

7. What is plane polarisation?

8. How do you confirm if a beam of light is polarised?

   • Pass it through a sheet of polaroid (or analyser) held in the path of the wave at 90 degrees to the wave and rotate it through 360 degrees. The light will be extinguished twice during the rotation.

9. Why can sound waves never be polarised?

10. What is Phase difference?

11. What are common properties of all EM waves?

    • (1) They are all transverse
    • (2) They all travel at the same speed in a vacuum
    • (3) They can all travel through a vacuum
    • (4) They can all be polarised

12. What is the order of the EM spectrum from longest to shortest wavelength?