Questions Related to spectra

Multiple choice physics spectra the electromagnetic spectrum electromagnetic spectrum electromagnetic waves

The decreasing order of wavelength of infrared, microwave, ultraviolet and gamma rays is

  1. Microwaves, Infrared, ultraviolet, gamma rays.

  2. Infrared, Microwaves, ultraviolet, gamma rays.

  3. ultraviolet, gamma rays, Infrared, Microwaves

  4. Microwaves, gamma rays, Infrared, ultraviolet

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The wavelength of the Electromagnetic waves is inversely proportional to the frequency of the wave. The frequency of the gamma rays is highest whereas the ultraviolet, Infrared and microwaves follow in decreasing order.
Therefore, the decreasing order of wavelengths will be opposite to the frequency order. So, the microwaves have the longest wavelength and the gamma rays have the smallest.

Microwave $>$ Infrared $>$ Ultraviolet $>$Gamma ray.

Multiple choice physics spectra the electromagnetic spectrum electromagnetic spectrum electromagnetic waves

Which of the following rays is emitted  by a human body?

  1. x-rays

  2. visible rays

  3. uvrays

  4. IR rays

  5. none of these

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

All bodies above absolute zero temperature emit electromagnetic radiation. The wavelength of radiation emitted depends on the temperature of the body. Most of the radiation emitted by the human body is mainly at the wavelength of 12 micron. The wavelength of infrared radiation is between 0.75 to 1000 micron (1 micron = 10-6 metres). Hence , the majority of radiation emitted by human bodies lie in the infrared region.

Multiple choice physics spectra the electromagnetic spectrum electromagnetic spectrum electromagnetic waves

The spectrum of molecular form the substance is called :

  1. band spectrum

  2. line spectrum

  3. absorption spectrum

  4. continuous spectrum

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In spectrum. Band spectra is the name given to groups of lines so closely spaced that each group appears to be a band, nitrogen spectrum. Band spectra, or molecular spectra, are produced by molecules radiating their rotational or vibrational energies

Hence the option A is the right answer

Multiple choice physics spectra the electromagnetic spectrum electromagnetic spectrum electromagnetic waves

M and N are two electromagnetic waves.
The ratio $\dfrac{wavelength of M}{wavelength of N}=10^5$. What could M and N be?

M N
A Microwaves Visible light
B Microwaves $\gamma$-rays
C $\gamma$-rays Microwaves
D Visible light Microwaves


  1. A

  2. B

  3. C

  4. D

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The wavelength of microwave is around 5 mm and wavelenght of visible around 500 nm

Multiple choice physics spectra the electromagnetic spectrum electromagnetic spectrum electromagnetic waves

Name the seven prominent colours of the white light spectrum in order of their increasing frequencies

  1. Violet, Indigo, Blue, Green, Yellow, Orange, Red

  2. Red, Orange, Yellow, Green, Blue, Indigo, Violet

  3. Red, Orange, Violet, Yellow, Green, Blue, Indigo

  4. Orange, Yellow, Green, Red, Blue, Indigo, Violet

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The range of frequencies from red to violet is 430-790 THz.