ICSE Class 10th Science Chapter 6 - spectrum Important Questions with Answers

Why is the colour red used as a sign of danger?

A wave has wavelength 50 Å.

1. Name the wave.
2. State its speed in vacuum.
3. State its one use.

The smoke from a fire looks white. Which of the following statements is true?

1) Molecules of the smoke are bigger than the wavelength of light

2) Molecules of the smoke are smaller than the wavelength of light.

To which regions of the electromagnetic spectrum do the following wavelengths belong: 
(a) 250 nm 
(b) 1500 nm 

Calculate the shortest wavelength of electromagnetic radiation present in Balmer series of hydrogen spectrum.

Speed of blue light in water is ______.

Infrared radiations are used in warfare. Explain with reason, why?

A ray of light is incident at 45° on an equilateral prism in the diagram below.

1. Name the phenomenon exhibited by the ray of light when it enters and emerges out of the prism.
2. State the cause of the above phenomenon mentioned by you.

Assertion (A): Ultraviolet radiations is scattered more as compared to the microwave radiations.

Reason (R): Wavelength of ultraviolet radiation is more than the wavelength of microwave radiation.

Below is an incomplete table showing the arrangement of electromagnetic spectrum in the increasing order of their wavelength. Complete the table:

1. Identify the radiation A.
2. Name the radiation used to detect fracture in bones.
3. Name one property common to both A and Radio waves.