$X$-rays are not used for radar purposes because:

An $X$-ray tube operates at $30 \ kV$. What is the minimum wavelength emitted in $\mathring{A}$? (Given: $h = 6.6 \times 10^{-34} \ J \cdot s$,$e = 1.6 \times 10^{-19} \ C$,$c = 3 \times 10^8 \ m/s$)

When $X$-rays from a Coolidge tube pass through an aluminum foil of thickness $0.3 \, mm$,$50\%$ of the $X$-rays are transmitted. If the potential difference between the target and the cathode is increased,the fraction of $X$-rays transmitted through the same foil will be .......

The shortest wavelength emitted from an $X$-ray tube depends on which of the following?

For the production of $X$-rays, the target should be made of

The shortest wavelength of $X-$rays emitted from an $X-$ray tube depends upon