X-ray
X-ray is a type of radiation known as electromagnetic waves. It helps in creating pictures of the inside of human body. These images show the different parts of the body in various shades of black and white. It is due to the difference in amount of absorption by various tissues in the body. As calcium in bones absorbs most of the X-rays, so bones look white in colour. Fat and other soft tissuesabsorb less and depicts grey colour. 

(i) To which part of the electromagnetic spectrum does a wave of frequency 2 X ${10}^{18}\mathrm{Hz}$ belong? 

(ii) What is the range of wavelength for X-rays? 

(iii) How are the X-rays produced? 

(iv) What are the techniques by which X-rays can bedetected? (v) Mention any two uses of X-rays.