Question

Which of the following forms of electromagnetic radiation has the longest wavelength? a) microwaves b) ultraviolet c) infrared d) radio-waves Rank the following types of electromagnetic radiation in order of decreasing energy. a) X-rays > Ultraviolet > Visible > Microwaves b) Microwaves > Visible > Ultraviolet > X-rays Microwaves > Ultraviolet > Visible > X-rays d) X-rays > Visible > Ultraviolet > Microwaves

Answer 1

3. d. Radio waves

Radio waves has the longest wave length with a range of 1 mm to 100 kilometer.

4. a) X ray > Ultraviolet > visible > microwave.

Explanation:-

The energy of an electromagnetic wave is given by the formula E = hc/ wavelength that means energy of a wave is inversely proportional to it's wavelength. Greater the wave length lower the energy.

Now wave length of the given order of wave are

X -Ray = 1 - 10 PM

Ultraviolet = 10 - 400 nm

Visible = 400 - 700 nm

Microwave = 10⁵ - 10⁸ nm

As we can see if we move downwards from x ray to microwave wavelength is increasing which means the energy is decreasing. Therefore X ray has highest energy and microwave has lowest energy among these four.

Please like the answer if it helped. Thank you. :)