(a) How are infrared waves produced? Why are these waves referred to as heat waves? Give any two uses of infrared waves.

OR

(b) How are X-rays produced? Give any two uses of these.

Identify the electromagnetic wave whose wavelengths range is from about

(a) $$10^{-12} \mathrm{~m}$$ to about $$10^{-8} \mathrm{~m}$$.

(b) $$10^{-3} \mathrm{~m}$$ to about $$10^{-1} \mathrm{~m}$$.

Write one use of each.