Light and Sound

Question 1

What are the 2 types of wave?

Answer 1

Transverse and longitudinal

Question 2

What are transverse waves used to show?

Answer 2

Light

Question 3

What are longitudinal waves used to show?

Answer 3

Sound

Question 4

What do waves transfer?

Answer 4

Energy (sometimes information) without transferring matter

Question 5

What is the highest point of a wave called?

Answer 5

A crest

Question 6

What is the lowest point of a wave called?

Answer 6

A trough

Question 7

What is the amplitude of a wave?

Answer 7

Height of wave from crest/trough to central x axis point

Question 8

What is the wavelength of a wave?

Answer 8

The distance between 2 successive crests/troughs

Question 9

What is frequency measured in?

Answer 9

Hertz

Question 10

What is the normal?

Answer 10

An imaginary line 90 degrees to the mirror

Question 11

What is the 1st law of reflection?

Answer 11

Angle of incidence = angle of reflection

Question 12

What is lateral inversion?

Answer 12

The apparent reversal of left and right in a mirror

Question 13

What is refraction?

Answer 13

When the direction of a wave is changed as it passes a median which has a different speed

Question 14

What is the formula for refractive index?

Answer 14

Sin(angle I )/ Sin(Angle R)

Question 15

What is the refractive index of glass?

Answer 15

1.5

Question 16

What is the refractive index of water?

Answer 16

1.3

Question 17

What are the units of refractive index?

Answer 17

Refractive index has not units!

Question 18

What is Total Internal Reflection?

Answer 18

When the angle of incidence is greater than the critical angle and all the light is reflected

Question 19

What is the critical angle?

Answer 19

When the angle of refraction is at 90o and angle of incidence is less than this, so angle of incidence now critical angle.

Question 20

Where can we see use of Total Internal Reflection?

Answer 20

Submarine periscopes and optical fibres

Question 21

What is diffraction?

Answer 21

When waves are evenly dispersed and scattered after passing through a gap or pushing through an obstacle.

Question 22

What are concave lenses?

Answer 22

Diverging, so when parallel light rays pass through, the refracted rays diverge

Question 23

What are convex lenses?

Answer 23

Converging, so when parallel light rays pass through, the refracted rays converge at the principal focus

Question 24

Do we draw lines on a virtual ray?

Answer 24

No

Question 25

What is a virtual ray?

Answer 25

A path along which light appears to travel travel but has actually not

Question 26

What is a real ray?

Answer 26

A path light has actually traveled down

Question 27

What are the spectrum of colours?

Answer 27

Red, Orange, Yellow, Green, Blue, Indigo, Violet

Question 28

What is the speed of light?

Answer 28

3x10^8m/s

Question 29

What is the speed of sound?

Answer 29

343m/s

Question 30

What are the 7 wave types?

Answer 30

Radio, micro, infra-red, light, UV, X-ray, gamma

Question 31

What is the Doppler Effect?

Answer 31

The apparent change in the frequency of a wave caused by the wave source and the observer

Question 32

What is the symbol for frequency?

Answer 32

Lamda (Upside down y)

Question 33

In terms of speed and sound, what is velocity equal to?

Answer 33

Wavelength x Frequency

Question 34

What would happen if you double frequency?

Answer 34

The pitch would go up by an octave

Question 35

What does the loudness of sound depend on?

Answer 35

Amplitude

Question 36

What does the pitch of sound depend on?

Answer 36

Frequency and wavelength