electromagnetic spectrum

Question 1

what is light?

Answer 1

. form of radiation
. electromagnetic wave
. electric and magnetic component
. the two components oscillate perpendicular to its direction of propagation

Question 2

what are the properties of EM wave ?

Answer 2

speed (v) - the rate of travel of a wave in a certain direction
frequency (f) - the number of complete waves generated per second (Hz)
wave length - the distance from one point on a wave to the same point on successive wave (m)
amplitude- max distance of a wave measured from the line of equilibrium to the peak or trough of a wave (m)

Question 3

what is the wave equation?

Answer 3

speed=frequency x wavelength

Question 4

why is the EM wave a transverse wave?

Answer 4

.vibration is at right angle to the direction of travel

.both electric and magnetic field vibrate perpendicular to the direction of propagation

Question 5

what is the property of a polarised wave?

Answer 5

. a polarised wave only oscillates in one direction

. polarisation can only happen for transverse waves

Question 6

what happens when you put 2 polarising filters parallel to each other?

Answer 6

. all the light gets through

Question 7

what happens when you put 2 polarising filters at right angle to each other?

Answer 7

. no light will get through

Question 8

what are the uses of polarised light ?

Answer 8

. polaroid sunglasses
.polarisation of radio and microwave signals
.LCD liquid crystal displays