Physics 1.5 Features of Waves

What are the two types of waves?

Transverse Longitudinal

What is a transverse wave?

A wave for which the oscillations are perpendicular to the direction of energy transfer.

What is a longitudinal wave?

A wave for which the oscillations are parallel to the direction of energy transfer.

Give two examples of transverse waves.

Electromagnetic waves Seismic s-waves

Give two examples of longitudinal waves.

Sound waves Seismic p-waves

What are the two parts of a longitudinal wave called?

Compressions and rarefactions.

What are the two parts of a transverse wave called?

Peaks and troughs.

What is a wave’s amplitude?

The maximum displacement of a point on a wave from its undisturbed position.

What is wavelength?

The distance from a point on a wave to the same position on the adjacent wave. Most commonly peak to peak or trough to trough.

What is the frequency of a wave?

The number of waves that pass a given point each second.

What is the unit used for frequency?

Hertz, Hz.

What is meant by a frequency of 200Hz?

200 waves pass a given point each second.

What is wave speed?

The speed at which energy is transferred through a medium.

What does a wave transfer?

Energy. Waves do not transfer matter.

State the equation used to calculate wave speed. Give appropriate units.

Wave Speed = Frequency × Wavelength Speed (m/s), Frequency (Hz), Wavelength (m).

What word is used to describe when a wave bounces off a surface?

Reflection.

What type of spectrum do electromagnetic waves form?

A continuous spectrum.

Order the types of electromagnetic radiation from lowest to highest frequency.

Radio waves Microwaves Infrared Visible Light Ultraviolet X-rays Gamma Rays

Which types of electromagnetic radiation have the longest and shortest wavelength?

Longest: Radio waves Shortest: Gamma rays

Which types of electromagnetic radiation have the lowest and highest energy?

Lowest: Radio waves Highest: Gamma rays

How do the speeds of EM radiation differ in a vacuum and in air?

Electromagnetic waves all travel at the same speed in a vacuum and in air.

What property of waves in different mediums causes refraction?

Velocity. Wave speed is slower in denser materials, causing refraction.

In which direction relative to the normal do waves refract when entering a denser medium?

They bend towards the normal. The angle of refraction is less than the angle of incidence.

What is a geostationary satellite and what are they used for?

A satellite that has the same period as the Earth and so remains in a fixed position relative to the Earth. Used for communications such as satellite TV signals./