X-rays Physics - X-rays

X-ray beam can be deflected:

1. By an electric field.
2. By a magnetic field.
3. By an electric field as well aa by a magnetic field.
4. Neither by an electric field nor by a magnetic field.

The energy of a photon of a characteristic X-ray from a Coolidge tube comes from:

1. The kinetic energy of the striking electron.
2. The kinetic energy of the free electrons of the target.
3. The kinetic energy of the ions of the target.
4. An atomic transition in the target.

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

Can X-rays be polarized?

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 a hydrogen atom emit characteristic X-rays?

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?

The electric current in an X-ray tube (from the target to the filament) operating at 40kV is 10mA. Assume that on an average, 1% of the total kinetic energy of the electron hitting hte target are converted into X-rays.

1. What is the total power emitted as X-rays
2. How much heat is produced in the target every second?

Find the energy, the frequency and the momentum of an X-ray photon of wavelength 0.10nm.

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 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?

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.

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