Which electromagnetic waves have the shortest wavelength and the highest frequency?

Gamma rays

Explanation:

The distance between two consecutive crests or trough is called the wavelength of electromagnetic wave. The number of oscillations per unit time is called the frequency of the wave.

There exists an inverse relationship between the frequency and the wavelength as

v = υ × λ    

Where

v is the speed of wave

υ is the frequency of wave

λ is the wavelength of the wave

So, the wave having shortest wavelength will have highest frequency. Gamma rays have shortest wavelength and the highest frequency. Its wavelength is approximately and its frequency is 10²¹ Hz.            

photocells convert light energy to electricity

the bal will not change its velocity.