What determines the hardness of the `X` - rays obtained from the Coolidge filament ?

One of the following wavelength is absent and the rest are present in the X-rays coming from a Coolidge tube. Which one is the absent wavelength?

One of the following wavelength is absent and the rest are present in the X-rays coming from a Coolidge tube. Which one is the absent wavelength?

One of the following wavelength is absent and the rest are present in the X-rays coming from a Coolidge tube. Which one is the absent wavelength?

The continuous x - ray spectrum obtained from a Coolidge tube is of the form

The continuous x - ray spectrum obtained from a Coolidge tube is of the form

State the effect of the following changes on the X rays emitted by Coolidge X-ray tube : Filament temperature is increased.

What is the nature of soft X-rays and hard X-rays ?

State the effect of the following changes on the X-rays emmited by Coolidge X-rays tube : (i) High voltage between cathode and anode is increased. (ii) Filament temperature is increased.