Waves

Question 1

what is a longitudinal wave and example?

Answer 1

waves that travel through vibrations of the median in direction of matter. e.g Sound.

Question 2

what is a Transverse wave and example?

Answer 2

waves that oscillate at 90 degrees of direction of energy and need no median to travel through. e.g Light.

Question 3

what is a progressive wave?

Answer 3

A wave that moves away from a source that oscillates.

Question 4

what is the radius angle of Pi

Answer 4

180 radius

Question 5

what is the radius angle of 2Pi/4

Answer 5

315 radius

Question 6

what is the equation involving speed wavelength and frequency?

Answer 6

speed=frequency*wavelength

Question 7

what is the wavelength of visible light?

Answer 7

3.7x10-7 to 7.4x10-7

Question 8

how do you work out frequency?

Answer 8

1/time

Question 9

Define amplitude?

Answer 9

displacement between peak and 0 line.

Question 10

define frequency?

Answer 10

complete oscillations per unit of time

Question 11

Describe two differences of transverse and longitudinal waves?

Answer 11

transverse waves can travel through a vacuum and oscillate at 90 degrees of direction of energy traveled.

Question 12

calculation for intensity?

Answer 12

(energy/time)power/area.

Question 13

If you decrease the amplitude of a wave by 4 what will happen to the intensity?

Answer 13

intensity will decrease by 16 because intensity is proportional two amplitude SQUARED.

Question 14

The angle of incidence is 30 the angle of reflection is?

Answer 14

30

Question 15

What size does a mirror have to be for you too see your self in it and why?

Answer 15

It has to be half your length because rays of light that enter your eyes from the mirror is reflect half the way down it.

Question 16

what is Snell’s law?

Answer 16

(refractive index of first material ) n1 x sin angle1 = n2 x sin angle2

Question 17

what is the calculation for refractive index not using Snell’s law?

Answer 17

refractive index= (the speed of light)speed of light in vacuum / speed of light in material.

Question 18

what is the speed of light?

Answer 18

299 792 458 m/s around to 3.00x10 to power of 8 m/s

Question 19

What is a polarised wave?

Answer 19

where light has been put through a polarising filter and is a single plane.

Question 20

How does a polarising filter make the light through it darker?

Answer 20

the light waves that enter the filter have many planes(oscillate at any angle from vertical to horizontal) but the filter absorbs all planes that the plane it wants and only emits the waves on that plane so every thing looks darker.

Question 21

what happens when you have two polariser one a 90 degrees from the other?

Answer 21

It is completely black no light can get through because they absorb both the vertical and horizontal planes of the light.

Question 22

what happens when you have three polariser one at 90 degrees from the first and the one in between at a angle of 45 degrees?

Answer 22

You can see through them again the second polariser emits the light at an angle of both vertical and horizontal planes so light of planes vertical or horizontal can get through.

Question 23

what is the frequency of visible light?

Answer 23

8x10 14 to 4x10 14