Q 01/05

In the mnemonic ROYGBIV for the colours of the rainbow, what does the I stand for?

A) Indigo

B) Ice blue

C) Ivory

D) Iris

Answer · why

A) Indigo

British schoolchildren learn the same order as 'Richard Of York Gave Battle In Vain', a nod to the Duke of York's death at the Battle of Wakefield in ...

Q 02/05

Newton first split the spectrum into five colours. Why did he later add two more to make seven?

A) To honour the seven days of creation

B) To match the seven known planets

C) To match the seven metals of alchemy

D) To match the number of musical notes in a major scale

Answer · why

D) To match the number of musical notes in a major scale

Newton was also the first person to use the word 'spectrum' in print for the band of colours, in 1671.

Q 03/05

Which colour of visible light has the longest wavelength?

A) Green

B) Violet

C) Red

D) Blue

Answer · why

C) Red

The human eye responds to wavelengths from roughly 380 to 750 nanometres, and this colour sits at the top of that range.

Q 04/05

The daytime sky is blue because of what physical effect, named after a British physicist?

A) Compton scattering

B) Doppler shift

C) Bragg diffraction

D) Rayleigh scattering

Answer · why

D) Rayleigh scattering

Lord Rayleigh's 1871 explanation is a textbook example of solving a physics problem by dimensional analysis alone.

Q 05/05

In the CMYK printing model, what does the K stand for?

A) Kobalt

B) Kelvin

C) Key

D) Kohl

Answer · why

C) Key

The black plate was the 'key' plate that the other three colour plates were aligned to.