Question

Wavelength of a colour of light for air is 6000˚A and in water the wavelength is 4500˚A. What is the speed of light in water.

Answer 1

speed of light in air considered 3x10^8

$c \div v = wavelength \: in \: air \: \div wavelength \: in \: water$

$v = 3 \times 10 {}^{8} \times 4500 \div 6000$

$v \: = 2.25 \times 10 {}^{8}$