physics

What are transverse waves?

Waves that oscillate ( move between two points) perpendicular to the direction of movment

What are longitudinal waves?

Waves that oscillate parallel to the direction of the wave movement

Whats an example of a transverse wave?

Ripples on the surface of water

Whats an example of longitudinal waves?

Sound waves travaling through

Whats amplitude

Maximum Displacment of a point on a wave away from its undisturbed position

Whats wave length?

Distance from one point on one wave to the equivalent point on the adjacent wave

Whats wave speed?

Speed at which the energy is transferred (or wave moves through a medium

Whats the formula that links wave speed frequency?

Wave speed +frequency x wavelength

What measurements would you need to take to find the speed of water ripples.

Measure the wavelength of the ripples and their frequency (counting the number of waves that pass a given point in a given time)

What four things can happen when a wave reaches a boundary beetween two materials?

• absorption

• Reflection

• Transmission

• Refraction

What happens to a waves energy when the wave is absorbed at a boundary?

Its energy is transferred to the energy stores of the material it is trying to cross into. Often transferred into thermal energy store of material.

What happens to a waves energy when its reflected?

The wave bounces back from the second material eg. A sound wave resulting in an echo or a light wave off a mirror.

What happens to a waves energy when its transmitted?

The wave carries on travelling through the second material eg. Light through a window the waves often undergo refraction.

What causes refraction?

Changes to a waves velocity in a different media resulting in a change of direction.

What’s the normal on a ray diagram?

An imaginary line at 90 degrees to the boundary between two materials

What happens to a waves that travels along the normal?

The wave isn’t refracted

What happens to wave fronts when a wave travels from a less dense to a more dense medium?

They get closer

Whats the use of radio waves?

Broadcasting and communication

What’s one use of radio waves?

Cooking and satellite transmissions

Whats one use for infrared radiation?

Heaters and night vision equipment

Whats one use of UV waves?

Fluorescent lights

Whats one use for x-rays?

Observing the internal structure of objects and materials and medical applicators

Whats the use of gamma rays?

Sterilising food and medical equipment

Whats the electromagnetic spectrum?

• radio waves

• Microwaves

• Infrared

• Visible light

• Ultraviolet

• X-rays

• Gamma rays

Whats one danger of microwaves?

Internal heating of body tissue

Whats one danger of infrared waves?

Skin burns

Whats one danger of uv waves?

Damage to surface cells and Blindness

Whats one danger of gamma rays?

Cancer, mutation