If the operating voltage of an $X$-ray tube is $50 \, kV$,then the velocity of the $X$-rays is . . . . .

An $X$-ray tube with a copper target emits a $Cu$ $K_{\alpha}$ line of wavelength $1.50 \ \mathring{A}$. What should be the minimum voltage through which electrons are to be accelerated to produce this wavelength of $X$-rays? $(h = 6.63 \times 10^{-34} \ \text{J}\cdot\text{s}, c = 3 \times 10^8 \ \text{m/s})$

At the time of a total solar eclipse,the spectrum of solar radiation would be:

If the cathode-anode potential difference in an $X$-ray tube is $10^5 V$,then the maximum energy of an $X$-ray photon can be:

Assertion: $X-$rays travel with the speed of light.
Reason: $X-$rays are electromagnetic rays.

The patient is asked to drink $BaSO_4$ for examining the stomach by $X$-rays because $X$-rays are