Sound and Optics Test

Question 1

What are musical notes

Answer 1

Rhythmic smooth change in sound waves

Question 2

What is general noise

Answer 2

Sound waves that vary in frequency without any pattern

Question 3

What is the range of sound your ears can detect

Answer 3

20-20000 Hz

Question 4

Sound waves travel through different substances…

Answer 4

at different speeds

Question 5

What happens when sound waves travel between two substances

Answer 5

The frequency does not change, but the speed of the wave may

Question 6

Where does the human ear hear best at

Answer 6

3000Hz

Question 7

What is echo sounding

Answer 7

pulses of high-frequency sound waves to help ships measure water depth

Question 8

How to work out depth (distance) in echo sounding

Answer 8

1/2 x speed x time

Question 9

What are sound waves over 20000Hz called?

Answer 9

Ultrasound

Question 10

What is an ultrasound scanner made up of

Answer 10

A transducer, control system and display screen

Question 11

What does the transducer do?

Answer 11

Produces and detects sets of ultrasound waves

Question 12

How do the ultrasound pulses work?

Answer 12

Reflected from the different tissue boundaries in its path

Question 13

Differences between X-rays

Answer 13

Can be used to scan softer areas, while x-rays usually scan harder parts. Non-ionising

Question 14

What can ultrasound be used for?

Answer 14

Scanning of humans, industrial imaging
Scanning of the eye

Question 15

line perpendicular to the mirror

Answer 15

normal line

Question 16

angle between the incident ray and the normal

Answer 16

angle of incidence

Question 17

angle between the reflected ray and the normal

Answer 17

angle of reflection

Question 18

angle of incidence in a plane mirror=

Answer 18

angle of reflection

Question 19

plane mirror is

Answer 19

virtual
upright
inverted

Question 20

what is reflection on a smooth surface aka

Answer 20

specular

Question 21

what is reflection on a rough surface aka

Answer 21

diffuse reflection

Question 22

when light enters a more dense medium, it is refracted…

Answer 22

towards the normal (angle of reflection is smaller)

Question 23

when light enters a less dense medium, it is refracted…

Answer 23

away from the normal (angle of a reflection is larger)

Question 24

the wavelength of colour increases from

Answer 24

Purple to red

Question 25

how does the colour of a surface change

Answer 25

you can change it by changing the colours of the pigments inside

Question 26

Translucent objects…

Answer 26

let light pass through but scatters or refracts the light

Question 27

transparent objects…

Answer 27

let all light that enters it pass through and doesn’t scatter or refract the light

Question 28

converging lenses make…

Answer 28

parallel rays converge to a focus point, known as the principal focus

Question 29

diverging lesnses make…

Answer 29

parallel rays diverge; the principal focus is on the ‘left’ side of the lens

Question 30

the distance from the centre of the lens to the principal focus is called the

Answer 30

focal length

Question 31

convex lenses form real images when

Answer 31

the object is further away than the principal focus to the lens

Question 32

convex lenses form virtual images when

Answer 32

the object is closer to the lens than the principal focus

Question 33

magnification

Answer 33

image height/object height

Question 34

cameras contain

Answer 34

converging lenses used to form real objects