P6- Waves

Question 1

what direction do waves transfer energy in?

Answer 1

the direction of travel

Question 2

what waves have sideways vibrations?

Answer 2

Transverse

Question 3

what waves have parallel vibration?

Answer 3

longitudinal waves

Question 4

what is wave speed?

Answer 4

Wave Speed = Frequency × Wavelength
The wave speed is the speed at which energy is be transferred (or the speed the wave is moving at).

Question 5

what do you use to measure the speed of sound?

Answer 5

Oscilloscope

Question 6

what do you use to measure the speed of water ripples?

Answer 6

a ripple tank

Question 7

what the 3 thing waves can be?

Answer 7

-Absorbed
-Transmitted
-Reflected

Question 8

what are electromagnetic waves?

Answer 8

Electromagnetic waves are transverse waves with a wide range of properties and uses. All objects are continually absorbing and emitting infrared radiation, affecting their temperatures. Part of Physics (Single Science)Light and the EM spectrum.

Question 9

what is refraction?

Answer 9

waves changing direction at a boundary

Question 10

what do ray diagrams show ?

Answer 10

the path of a wave

Question 11

how are radio waves made?

Answer 11

by oscillating charges

Question 12

what are radio waves mainly used for?

Answer 12

communication

Question 13

what uses microwaves?

Answer 13

-satellites
-microwave ovens

Question 14

what can infrared radiation be used for?

Answer 14

to increase or monitor temperature

Question 15

what do fibre optic cables use to transmit data?

Answer 15

visible light

Question 16

investigating infrared radiation:
-practical

Answer 16

Place an empty Leslie cube on a heat-proof mat.
Boil water in a kettle and fill the Leslie cube with boiling water.
Wait a while for the cube to warm up, then hold a thermometer against each of the four vertical faces of the cube. You should find that all four faces are the same temperature.
4) Hold an infrared detector a set distance (e.g. 10 cm) away from one of the cube’s vertical faces, and
record the amount of IR radiation it detects.
Repeat this measurement for each of the cube’s vertical faces.
the detector at the same distance from the cube each time.
6) You should find that you detect more infrared radiation from the black surface
than the white one, and more from the matt surfaces than the shiny ones.
As always, you should do the experiment more than once, to make sure your results are repeatable (p.4).
8) It’s important to be careful when you’re doing this experiment. Don’t try to move the cube when full of boiling water — you might burn your hands. And be careful if you’re carrying a full kettle your mate won’t thank you if you spill boiling water into their bag (or down their back).

Question 17

what are the dangers of electromagnetic waves?

Answer 17

infrared radiation is felt as heat and causes skin to burn; visible light from a laser which is very intense can damage the retina at the back of the eye; ultraviolet can damage skin cells and lead to skin cancer and damage the eyes, it can cause skin to age prematurely; X-rays damage cells inside the body.