The speed of light in a vacuum is
3 million km per second
30 km per second
30 000 km per second
300 000 km per second

Sound waves above 20 000HZ or just out of the range of human hearing are known as XRays
Ultrafast Waves
Light Waves
Ultrasonic Waves

The speed of light in glass is 2 million km per second
20 km per second
20 000 km per second
200 000 km per second

When light passes through a prism and split into different spectral colours it has undergone Dispersion
Diffusion
Interference
Diffraction

Which of these materials has the highest refractive index of 2.42 ? Diamond
Glass
Water
Perspex

The speed of sound in air is around 30 metres per second
5000 metres per second
1400 metres per second
330 metres per second

The speed of sound in water is around 30 metres per second
5000 metres per second
1400 metres per second
330 metres per second

When identical waves overlap they may reinforce or cancel each other out this is known as Dispersion
Diffusion
Interference
Diffraction

The ratio of the speed of light in a vacuum to the speed of light in a material is known as Relational Index
Reflective Index
Dispersive Index
Refractive Index

The speed of sound in concrete is around 30 metres per second
5000 metres per second
1400 metres per second
330 metres per second

