X-rays Physics - X-rays

Why is exposure to X-rays injurious to health but not exposure to visible light, when both are electromagnetic waves?

Find the cutoff wavelength for the continuous X-rays coming from an X-ray tube operating at 30kV.

When 40kV is applied across an X-ray tube, X-ray is obtained with a maximum frequency of 9.7 × 10¹⁸Hz. Calculate the value of Planck constant from these data.

Find the maximum potential difference which may be applied across an X-ray tube with tungsten target without emitting any characteristic K or L X-ray. The energy levels of the tungsten atom with an electron knocked out are as follows.

Cell containing vacancy	K	L	M
Energy in keV	69.5	11.3	2.3

In a Coolidge tube, electrons strike the target and stop inside it. Does the target get more and more negatively charged as time passes?

Can X-rays be used for photoelectric effect?

If the operating potential in an X-ray tube is increased by 1%, by what percentage does the cutoff wavelength decrease?

Characteristic X-rays may be used to identify the element from which they are being emitted. Can continuous X-rays be used for this purpose?

The X-ray coming from a Coolidge tube has a cutoff wavelength of 80pm. Find the kinetic energy of the electrons hitting the target.

Can X-rays be polarized?

Can a hydrogen atom emit characteristic X-rays?

The electron beam in a colour TV is accelerated through 32kV and then strikes the screen. What is the wavelength of the most energetic X-ray photon?

The X-ray beam emerging from an X-ray tube:

1. Is monochromatic.
2. Has all wavelengths smaller than a certain maximum wavelength.
3. Has all wavelengths greater than a certain minimum wavelength.
4. Has all wavelengths lying between a minimum and a maximum wavelength.

50% of the X-ray coming from a Coolidge tube is able to pass through a 0.1mm thick aluminium foil. The potential difference between the target and the filament is increased. The thickness of the aluminium foil that will allow 50% of the X-ray to pass through will be:

1. zero
2. < 0.1mm
3. 0.1mm
4. > 0.1mm

Visible light passing through a circular hole forms a diffraction disc of radius 0.1mm on a screen. If an X-ray is passed through the same setup, the radius of the diffraction disc will be:

1. zero
2. < 0.1mm
3. 0.1mm
4. > 0.1m

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

1. 25pm
2. 50pm
3. 75pm
4. 100pm

When a Coolidge tube is operated for some time it becomes hot. Where does the heat come from?

An X-ray tube operates at 40kV. Suppose the electron converts 70% of its energy into a photon at each collision. Find the lowest there wavelengths emitted from the tube. Neglect the energy imparted to the atom with which the electron collides.