Flashcards

Physics revision

11-came English 46 cards

Cards in this deck (46)

1What are waves used for?Waves are used to transfer energy or information
2Draw and describe a transverse wave
3Draw and describe longitudinal waves
4What are mechanical waves?They are waves that have vibrations that travel through a medium, some are transverse and some are longitudinal E.g sound waves
5What are electromagnetic waves?They are waves that do not require a medium meaning they can travel through a vacuum, these waves are always transverse E.g. light, radio, microwave
6Draw and describe how you make straight plain waves
7Draw and describe how you make circular waves
8What is the wave speed equation and what is the speed equation?Wave speed (m/s) = frequency (Hz) * wavelength (m)
and
speed (m/s) = distance (m) / time (s)
9Label all of the parts of a wave
10What is frequency?The number of waves that pass every second, the unit of frequency is Hertz (Hz)
11What is wavelength?The distance from one point on a wave to the same point on the next wave
12What is amplitude?The distance between the peak/trough and the rest position
13What is the normal?A line perpendicular to the mirror
14What is the angle of incidence?The angle between the incident ray and the normal
15What is the angle of reflection?The angle between the reflected ray and the normal
16What is the law of reflection?Angle of incidence = angle of reflection
or
i = r
17Draw the diagram to show the law of reflection
18What is an image in a plain (flat) mirror?It is laterally inverted, upright and virtual
19Draw the diagram to show the image formation by a plain mirror
20Describe refractionAs a wave moves enters a denser material it bends towards the normal, as the wave leaves the denser material it bends away from the normal
21Draw a diagram to show refraction in a perspex block $Draw a diagram to show refraction in a perspex block$
22Describe refraction in deep to shallow waterWater waves slow down as they move from deep to shallow water. They will bend towards the normal. When they move from the shallow water to the deep water, they speed up and bend away from the normal
23Draw a diagram to show refraction in deep to shallow water $Draw a diagram to show refraction in deep to shallow water$
24Describe refraction in a triangular prismWhite light is made up of all of the colours of the spectrum. Each colour refracts by a different amount. When white light is passed through a triangular prism it causes the colours to disperse (spread out) into the colours of the spectrum (ROYGBIV)
25Draw a diagram to show refraction in a triangular prism $Draw a diagram to show refraction in a triangular prism$
26What is diffraction?Diffraction is the spreading out of waves as it moves past an obstacle OR through a gap
27Draw an example of diffraction $Draw an example of diffraction$
28Draw another example of diffraction $Draw another example of diffraction$
29Sound wavesSound waves need a medium to travel through meaning that they cannot travel through a vacuum. These can be longitudinal or transverse waves.
Human hearing = 20 Hz - 20,000 Hz
30What is the reflection of sound and when will the reflection of sound not occur (give two examples)The reflection of sound is an echo.
If a wall is covered in fabric, no sound will be absorbed therefore it cannot be reflected and there is no echo.
If a wall is not smooth, the reflected sounds are scatters and therefore there is no echo.
31Describe the refraction of sound and give an exampleDue to sound being faster in warmer air, refraction takes place at the boundaries between layers of air at different temperatures
32What is the reflection of light?A mirror
33What is the refraction of light?A coin placed at the bottom of a beaker containing water, looks like it is higher up
34What is diffraction of sound?Speaking into a microphone, the sound cam be heard round corners
35Describe pitch and volumeThe pitch of a note increases with the frequency
The volume is increased with the amplitude
36Describe the properties of E.M WavesAll of them are transverse
They can all travel in a vacuum
They all have the speed of 3 * 10 to the power of 8 m/s in a vacuum
They can be reflected, refracted and diffracted
wave speed equation can be used to work out frequency or wavelength
Higher frequency waves have higher energy
37Name all of the EM waves in order of wavelengthRadio - red
Microwave - meat
Infrared - is a
Visible light - very
Ultraviolet - unusual
X-ray - xmas
Gamma - gift
38Where should you revise: Visible light, optical fibres, microwaves, infrared radiation, radio waves and the Hazards of EM WavesYour revision book
39What is the doppler effect?A change in the wavelength + frequency observed, the doppler effect is due to the motion of the source of the waves
40Towards the observer...short wavelength, high frequency, high pitched sound
41Away from observer...long wavelength, low frequency, low pitched sound
42What are absorption lines?Parts of the light spectrum that are absorbed by certain atoms e.g hydrogen. These form dark lines within the colour spectrum.
Changes in the wavelength of the light waves causes the position of these lines to shift
43Describe red shiftLight from distant galaxies show the dark spectral absorption lines shifted to the red end of the spectrum. This is called Red shift. This means that the wavelengths are longer and the frequency is lower. This shows in turn, that galaxies are moving away from us, and that the universe is expanding. The further away the galaxy, the more red shift there is, therefore the faster they are expanding.
REMEMBER: THE ABSORPTION LINES ARE SHIFTED TO RED END OF THE SPECTRUM NO OBJECT DOES NOT LOOK RED
44Describe the big band theoryThe universe started with a massive explosion, from a very small point and evidence NOT PROOF of this is Red shift and CMBR
45What is CMBR (Caitlyn may bite rabbits)?Cosmic Microwave Background Radiation:
High energy gamma radiation thought to be caused by Big Band explosion and has existed in space since then. As the universe expanded, waves stretched in wavelength to microwaves.
46Describe the future of the universeThe future of the universe depends on the density of the universe. Under a certain density, the universe will expand forever, stars and life will eventually die out (Big Yawn)
Over a certain density, the universe will stop expanding and reverse (Big Crunch)