Topic 1- Waves And Optics

Question 0

If a rock were to drop into a pond with a duck siting in it, would the duck move with the wave?

Answer 0

No it would not, the rock transfers energy from it to the duck

Question 1

What is a wave a transfer of?

Answer 1

Energy

Question 2

What is the equation for distance involving speed and time?

Answer 2

Distance (d) = speed (v) x time (t)

Question 3

What is the experiment used to determine the speed of sound, which involves two microphones and an electronic timer

Answer 3

Two microphones are placed a distance apart from each other. An electronic timer is connected to both of these.
A loud sound is made, when this sound reaches microphone A the electronic timer starts. When it reaches microphone B the electronic timer stops.
Then using the distance between the microphones and the time on the electronic timer we can determine the speed of the sound.

Question 4

What is the speed of radio, electronic signals and light in air?

Answer 4

3x108 m/s

three times ten to the power of 8 metres per second/ 300 million m/s

Question 5

Why will light reach your eyes almost instantly?

Answer 5

It’s speed is so fast

Question 6

Tell me the comparison between the speed of light and the speed of sound?

Answer 6

The speed of light (3x10 8 m/s) is MUCH faster than the speed of sound (340 m/s) which is MUCH slower.

Question 7

What is the equation involving velocity, displacement and time?

Answer 7

Displacement (s) = velocity (v) x time (t)

Question 8

What is the speed of sound in air?

Answer 8

340 m/s

Question 9

What is frequency?

Answer 9

The number of waves that pass a point in 1 second

Question 10

What is frequency measured in?

Answer 10

Hertz (Hz)

Question 11

What is meant by the wavelength?

Answer 11

The horizontal distance between two adjacent crests or troughs. ( the distance from one point on a wave to the same point on the next)

Question 12

What is the units of wavelength?

Answer 12

Metres (m)

Question 13

What is meant by amplitude?

Answer 13

The size from the crest or trough of a wave to the zero line / zero position

Question 14

What is amplitude measured in?

Answer 14

Metres (m)

Question 15

If the waves are smaller, what does that mean the amplitude is?

Answer 15

The amplitude is low

Question 16

If the size of the wave is large what does that mean the amplitude is?

Answer 16

The amplitude is high

Question 17

If there are a lot of waves that means the frequency is?

Answer 17

The frequency is high

Question 18

Of there are not a lot of waves that means the frequency is?

Answer 18

The frequency will be low

Question 19

What is meant by the period?

Answer 19

The period is the time it takes for a wave to pass a certain point

Question 20

What is the units for period?

Answer 20

Seconds (s)

Question 21

What is speed?

Answer 21

The distance travelled by a subject per unit time

Question 22

True or False?
A longitudinal wave is one in which the particles making up the wave vibrate in a parallel motion to the direction the wave is travelling?

Answer 22

TRUE

Question 23

Which way dot he particles move in a longitudinal wave?

Answer 23

Back and forth

Question 24

Give an example of a longitudinal wave?

Answer 24

Sound waves

Question 25

In a transverse wave do the particles making up the wave vibrate perpendicularly or parallel to the direction of the wave?

Answer 25

Perpendicularly

Question 26

Give an example of a transverse wave?

Answer 26

Radio waves

Question 27

What is the calculation involving speed, wavelength and frequency of a wave?

Answer 27

Speed (v) = frequency (f) x wavelength (lambda)

Question 28

What is the order of the members in the electromagnetic spectrum?

Answer 28

``` Gamma (girls) X-rays (xilaphobic) Ultra-violet (understand) Visible light (Volkswagens) Infrared (in) Microwaves (men) TV and Radio waves (rude) ```

Question 29

Can light be reflected?

Answer 29

Yes, light can be reflected

Question 30

What is the relationship between the angle of incidence and the angle of reflection?

Answer 30

Angle of incidence = angle of reflection

Question 31

State the principle of reversibility of a ray path

Answer 31

If the direction of a ray of light is reversed it will follow the same path but in the opposite direction.

Question 32

What are cute bed reflectors used for?

Answer 32

To increase the power of a received signal from a satellite or other source

Question 33

What is the focus on a curved reflector?

Answer 33

The point where the curves shape collects the signals into one place

Question 34

Why is the detector of a curved reflector placed at the focus?

Answer 34

So the detector receives a powerful signal

Question 35

In a transmitting curves reflector where is the source if the signal placed?

Answer 35

The focal point (the focus)

Question 36

When the signal is reflected in a transmitting curves reflector what are the beams of signal?

Answer 36

The beams of signal produces will be parallel

Question 37

What is an example of an application of curved reflectors used in telecommunication?

Answer 37

3 satellites in space, placed along the equator.

Question 38

TRUE OR FALSE? | The satellites above the earth continuously move

Answer 38

FALSE | They are geostationary, meaning they stay above the same position in the Earth's surface

Question 39

What is total internal reflection?

Answer 39

When the angle of in essence is bigger than the critical angle, no light escapes; all light is reflected back into the Perspex.

Question 40

What is meant by the critical angle?

Answer 40

When the angle of incidence is 42° and some light escapes at 90° to the normal line. This is called the critical angle.

Question 41

What is an optic fibre?

Answer 41

A thin thread like piece of glass along which light can travel.

Question 42

TRUE OR FALSE | Each optic fibre is about the thickness of a human hair.

Answer 42

TRUE | each optic fibre is about the thickness of a human hair

Question 43

Why are optic fibres coated with a thin layer of cladding?

Answer 43

To prevent any light escaping or passing through the sides to another fibre in the bundle

Question 44

What is meant by the refraction of light?

Answer 44

Refraction is the change in speed and sometimes (when angle of incidence is not equal to 0°) direction of a wave due to a change in its transmutation medium

Question 45

Explain what happens when a ray of light passes through glass

Answer 45

When a ray of light passes from air into glass, it slows down and refracts towards the normal line. As light passes from glass to site it speeds up and refracts away from the normal line.

Question 46

What is the calculation involving power and focal length?

Answer 46

``` Power= 1 Focal length(f) Focal length= 1 Power(p) ```

Question 47

What is the unit of power?

Answer 47

A dioptre (D)

Question 48

What is the unit of focal length?

Answer 48

Metre (m)

Question 49

TRUE OR FALSE | A converging lens has a negative power

Answer 49

FALSE | A converging lens has a positive power

Question 50

TRUE OR FALSE | A diverging lens has a negative power

Answer 50

TRUE | A diverging lens has a negative power

Question 51

What can and can't short sighted people see

Answer 51

CAN: Near objects CAN NOT: Far away objects

Question 52

What can an can't lob sighted people see?

Answer 52

CAN: Far away objects CAN NOT: Near objects

Question 53

TRUE OR FALSE | If someone has short sightedness the image is focused in front of the retina

Answer 53

TRUE

Question 54

TRUE OR FALSE | Is someone has long sightedness the image is focused behind the retina

Answer 54

TRUE

Question 55

Where is an image ideally supposed to focus inside the eye?

Answer 55

The retina

Question 56

What type of lens can cured far sightedness?

Answer 56

A convex lens

Question 57

What type of lens can cure short sightedness?

Answer 57

A concave lens