Other pages in this set

Page 2

Preview of page 2

Page 3

Preview of page 3

Here's a taster:

P1 B: REVISION NOTES.
PIB5.1 Electromagnetic Spectrum
KEY POINTS:
1. The EM spectrum (in order of increasing wavelength) is:
Gamma & X rays
UV
Visible
Infra-Red
Microwaves
Radio.
2. All electromagnetic waves travel through space at a speed of 300 million m/s
3. Wave speed= wavelength X frequency
WAVELENGTH
The energy electromagnetic waves transfer depends on the wavelength of the waves, which
is why different wavelengths have different effects.…read more

Page 4

Preview of page 4

Here's a taster:

P1 B: REVISION NOTES.
PIB5.2 Gamma Rays & X-rays
KEY POINTS:
1. X-rays and gamma radiation are absorbed by dense materials in bone and by
metal.
2. X-rays and gamma radiation damage living tissue when they pass through it.
3. X-rays are used in hospitals to take radiographs.
4. Gamma rays are used to kill harmful bacteria in food, sterilising surgical
equipment & to kill cancer cells.…read more

Page 5

Preview of page 5

Here's a taster:

P1 B: REVISION NOTES.
PIB5.3 Light & UV Radiation
KEY POINTS:
1. UV radiation is in the EM spectrum between violet light and X-radiation.
2. UV radiation has a shorter wavelength than light.
3. UV radiation harms the skin & eyes
UV RADIATION
Makes some chemicals emit light
Harmful to human eyes & could cause blindness
Smaller wavelengths than light
- Too much exposure could cause sunburn and skin cancer.…read more

Page 6

Preview of page 6

Here's a taster:

P1 B: REVISION NOTES.
PIB5.4 Infra-red, Microwaves & radio waves
INFRA REO RADIA TION
All objects emit infra-red radiation
The hotter the object the more of it will be emitted
It is absorbed by skin and can damage the cells because it heats them up.
MICROWAVES
They have a shorter wavelength than radio waves; which is why they are called this.…read more

Page 7

Preview of page 7

Here's a taster:

P1 B: REVISION NOTES.
PIB5.5 Communications
KEY POINTS:
1. The use we make of radio waves depends on the frequency of the waves
2. Visible light and infra-red radiation are used to carry signals in optical fibres.
RADIO COMMUNICA TlONS
Radio & microwave spectrum is divided into frequency bands. The use of these
waves depends on the frequency range
THE HIGHER THE FRQUENCY THE ...…read more

Page 8

Preview of page 8

Here's a taster:

P1B: REVISION NOTES.
PIB5.6 Analogue & Digital signals
DIAGRAM
(a)
Analogue
1--1J'""--;(--+-+-----\--C~_signal
(b)
1
r-----
o
Time
DIGITAL
A sequence of pulses, the voltage level of each pulse is either high or low with no in between
levels mobile phone and computers use digital signals.
ANaLOGUE
A continuesly varying wave from zero to the maximum value, an example is a microphone.
SENDING SIGNALS
Sending signals · to send an analogue
The waves we use to carry a signal are called carrier waves.…read more

Comments

No comments have yet been made

Similar Physics resources:

See all Physics resources »See all resources »