Chapter 4 - Waves

Question 1

Wave speed equation

Answer 1

Frequency X Wavelength

F X W (weird h symbol)

Question 2

Wavelength equation

Answer 2

Wave speed / Frequency

Wave speed
———————
Frequency

Question 3

Frequency

Answer 3

Wavespeed
——————
Wavelength

C / W

Question 4

Frequency with time

Answer 4

Frequency = 1
——-
T

T= period

Question 5

What would happen if both filters were aligned in the same way?

Answer 5

Polarised light will travel through both polariser. The light wave will only vibrate in one direction.

Question 6

What if the polarisers were at different angles?

Answer 6

If polariser one is horizontal the vertical polarised light wave will only vibrate in one direction which will have maximum light but because the second polariser is at a 90 degrees angle no light will travel through, the light wave will become unpolarised (incident beam) it will then allow light to spread out in all directions which will reduce the light source a lot which for us there will be no light shown.

Question 7

Displacement

Answer 7

Distance in a given direction

Question 8

Amplitude

Answer 8

Maximum displacement of a vibrating particle for a transverse wave it is distance from the middle to the peak of the wave.

Question 9

Wavelength

Answer 9

Least distance between two adjacent vibrating particles with the same displacement and velocity at the same time

Question 10

One complete cycle of a wave

Answer 10

When a vibrating particle is displaced unit is return to its stored.

Question 11

Frequency

Answer 11

Numb of cycles of wave that pass a point per second

Question 12

Period

Answer 12

Time for one complete wave to pass a fixed point.

Question 13

Distance speed and time

Answer 13

Distance / speed = time
Distance = speed x time
Speed = distance / time

Question 14

Transverse wave

Answer 14

Waves which the direction of vibration is perpendicular to the direction in which the wave travels

Question 15

Longitudinal

Answer 15

Waves in which the direction of vibration of particles is parallel to along the direction in which the waves travels.

Question 16

Plane polarised

Answer 16

Transverse waves that vibrate in one plain only

Question 17

Unpolarised

Answer 17

If the vibrations change from one plane to another the waves are unpolarised.

Question 18

Unpolar to polar slit board

Answer 18

unpolarised waves travelling on a rope. When they
pass through a slit in a board, they become polarised
because only the vibrations parallel to the slit pass through it.

Question 19

Unpolar into two polar

Answer 19

If unpolarised light is passed through two polaroid filters, the
transmitted light intensity changes if one polaroid is turned relative to
the other one. The filters are said to be crossed when the transmitted
intensity is a minimum. At this position, the polarised light from the
first filter cannot pass through the second filter, as the alignment of
molecules in the second filter is at 90° to the alignment in the first
filter. This is like passing rope waves through two letter boxes at right
angles to each other,