Question

Compare green and red light from the visible spectrum. which has: the longer wavelength? the greater frequency? the greater energy?

Answer 1

The spectrum goes as follows:
red, orange, yellow, green, blue, indigo and violet
Red has the lowest frequency.
Since frequency is inversely proportional to the wavelength, therefore, red has the longest wavelength.

Now, consider, the equation:
E = (hc) / lambda
Since the energy is inversely proportional to the wavelength, therefore, red will have the lowest energy.

Based on this, for the mentioned question:
1- Red has longer wavelength
2- Green has greater frequency
3- Green has greater energy

Answer 2

Red light will have the longer wavelength (in fact, has the longest wavelength in the visible spectrum). As frequency is the inverse of wavelength, this means that green will have the greater frequency. In addition, since frequency and energy have a direct relationship, green light will also have the greater amount of energy.