Waves

Question 1

What is a wave?

Answer 1

An oscillation (vibration) that transfers energy from one place to another.

Question 2

What is a transverse wave?

Answer 2

A wave that oscillates at right angles to the direction that energy is transferred.

Question 3

What are some examples of transverse waves?

Answer 3

Water waves, light, Mexican waves, radio waves and microwaves.

Question 4

What is a longitudinal wave?

Answer 4

A wave that oscillates in the same direction that energy is transferred.

Question 5

What is a prime example of a longitudinal wave?

Answer 5

Sound-waves.

Question 6

What is the highest point on a transverse wave called?

Answer 6

The peak (or crest).

Question 7

What is the lowest point on a transverse wave called?

Answer 7

The trough.

Question 8

What is the point on a longitudinal wave where it is spread out called?

Answer 8

A rarefaction.

Question 9

What is the point on a longitudinal wave where it is close together called?

Answer 9

A compression.

Question 10

What is wavelength?

Answer 10

The distance between one point on a wave and the same point on the next wave. It is often easiest to measure from the peak or trough of one wave to the other.

Question 11

What is amplitude?

Answer 11

The height from the peak or trough to the middle (always equal).

Question 12

What is the formula for calculating the wave’s speed?

Answer 12

V=D/T - Velocity (m/s) = distance (m) divided by time (secs).

Question 13

What is frequency?

Answer 13

The number of waves a second.

Question 14

What is the formula for frequency?

Answer 14

f=N/t - frequency (Hz) = number divided by time (secs)

Question 15

In what order from fastest to slowest would sound travel through the following materials: rubber, foam, brick and air?

Answer 15

Brick, rubber, foam and air.

Question 16

In what environment do sound waves travel the quickest?

Answer 16

In dense solids, the close-together particles can transfer the energy faster as they vibrate.

Question 17

What is a light year?

Answer 17

The distance traveled by light in a year.

Question 18

How would you conduct an experiment on light reflecting off mirrors?

Answer 18

First you draw a horizontal line on paper where the mirror stands up. Then draw a vertical line protruding out of the middle of the previous one to mark 90 degrees. After this set up, use a protractor to systematically turn the light around a range of different degrees. Finally, mark the places where the reflected beams were on the paper, and measure the degrees between the mark and the ninety degrees line.

Question 19

How does shining light onto a mirror work?

Answer 19

The angle of reflection is equal to the angle of incidence.

Question 20

What does luminous mean?

Answer 20

Giving off light / bright or shining.

Question 21

What does luminosity mean?

Answer 21

How luminous an object is - (the brightness).

Question 22

What does transparent mean?

Answer 22

Allowing light to pass through.

Question 23

What does translucent mean?

Answer 23

Allowing light - but not detailed shapes - to pass through.

Question 24

What does opaque mean?

Answer 24

Not allowing light to pass through.

Question 25

How would you conduct an experiment measuring the speed of sound?

Answer 25

Measure a reasonably long distance with a trundle wheel (minimum 100 metres). Put you and a volunteer at either end of that distance. You shout and put up your hand at the exact same moment. The volunteer starts a stopwatch when he sees your hand rise, and stops it when he hears you shout. Divide the distance by the time to work out the speed.

Question 26

What are the radiation safety precautions?

Answer 26

Time (spend little time as possible exposed), distance (don’t be near the radiation as much as possible) and shielding (materials that act as a barrier between you and the radiation.

Question 27

What protects you from gamma waves?

Answer 27

Barriers of lead, concrete or water.

Question 28

How does noise cancellation work?

Answer 28

The original noise is canceled or not heard because of the opposite sound waves being produced. This is usually done by a microphone that analyses the ambient surrounding sounds and generates the opposite of them.

Question 29

What are some advantages of fossil fuels?

Answer 29

It is cost-effective, can generate a lot of electricity, can be found easily and there is a plentiful supply (despite being finite).

Question 30

What are some disadvantages of fossil fuels?

Answer 30

It is not a renewable energy source, it pollutes the environment and they can be dangerous if used irresponsibly.

Question 31

What are some advantages of nuclear power?

Answer 31

It is a clean energy source, it creates jobs (nearly half a million), it is reliable so that if other energy sources fail, we can always use this one.

Question 32

What are some disadvantages to nuclear energy?

Answer 32

Nuclear power is very dangerous if misused, it generates radioactive waste that is hard to get rid of and Uranium is not a renewable material.