Waves and the Electromagnetic Spectrum

Frequency

________ is the number of waves passing a point in a second.

Amplitude

________ is the distance from the undisturbed position to the peak or trough of a wave.

Transverse waves

________ can move in liquid or solid, but not as a gas.

wavefront

A(n) ________ is a method of picturing waves from above.

X rays

________- used to photograph bones because they can penetrate soft tissues but not bone.

Microwaves

________- used for satellite communications as ________ can penetrate earths atmosphere.

Wavelength

________ and frequency are inversely proportional, meaning that increases in ________ are a decrease in frequency and vice versa.

higher frequency

A(n) ________ means that there is more radiation energy (more ionising, harmful to cells)

arrow

The ________ shows direction, sometimes being called a ray.

Gamma

________ rays- used to sterilise medical tools because ________ kills bacteria.

Microwave dangers

________- possible heat damage to internal organs.

Longitudinal

________- waves where particles oscillate parallel to the direction of energy transfer.

minimum displacement

It is the maximum or ________ from the undisturbed position.

Ultraviolet

________- used for detecting security ink because if fluoresces with ________ lighting.

Radiation

________ with lower energy is better for communications and less harmful to humans.

time period

The ________ is the time taken for a single wave to pass a point.

Electromagnetic waves

________ are transverse waves that transfer energy from the source of the waves to an absorber.

Pressure waves

________ caused by repeated movements in a liquid or gas.

Energy transfer

________ is in the same direction as the wave motion.

Wavelength

________ is the distance from one point on the wave to the same point on the next wave.

X rays

________ dangers- kills cells, mutations, cancer.

transverse

waves where particles oscillate perpendicular to the direction of energy transfer

longitudinal

waves where particles oscillate parallel to the direction of energy transfer

Radio waves

used for long-range communications as they can be reflected from Earths atmosphere

Microwaves

used for satellite communications as microwaves can penetrate earths atmosphere

microwave dangers

possible heat damage to internal organs

Infrared waves

used for optical fibre communication because they can undergo total internal reflection

infrared dangers

skin burns

Visible light

used for taking photos and videos as cameras are set up to detect visible light

visible light dangers

bright light causes eye damage

Ultraviolet

used for detecting security ink because if fluoresces with ultraviolet lighting

ultraviolet dangers

eye damage, sunburn, skin cancer

X-rays

used to photograph bones because they can penetrate soft tissues but not bone

X-rays dangers

kills cells, mutations, cancer

Gamma rays

used to sterilise medical tools because gamma kills bacteria

gamma rays dangers

kills cells, mutations, cancer

transverse waves

waves where particles oscillate perpendicular to the direction of energy transfer

longitudinal waves

waves where particles oscillate parallel to the direction of energy transfer

transverse wave features

* energy transfer is in the same direction as the wave motion
* transfer energy but not particles
* transverse waves can move in liquid or solid, but not as a gas
* some of them can move in a vacuum

longitudinal waves features

* energy transfer in the same direction as motion of the wave
* transfer energy but not particles
* can move in solids, liquids and gases
* cannot move in a vacuum

transverse waves examples (4)

* ripples on water
* guitar string vibrations
* S-waves
* electromagnetic waves

longitudinal waves examples (3)

* sound waves
* P-waves
* pressure waves caused by repeated movements in a liquid or gas

em wave properties

* transverse
* can travel through a vacuum
* travel at the same speed in a vacuum