ICSE solutions for Physics [English] Class 10 chapter 5 - Spectrum [Latest edition]

Light of different colours is deviated through different angles, by a prism. Explain the reason.

Which colour of white light is deviated most.

Which colour of white light is deviated at least?

Give a reason, why the violet colour of white light deviated most and red colour of white light deviated least.

What is understood by the term dispersion of light? What is its cause?

Name the region beyond  the red end  of the spectrum.

In the atmosphere which colour of light gets scattered the least?

Which characteristic property of light is responsible for the blue colour of the sky?

Write three conditions necessary to obtain a pure spectrum on a screen. Name the instrument in which the conditions stated by you are fulfilled.

Name any two electromagnetic waves which have a frequency higher than that of violet light. State one use of each.

How will you investigate the existence of the radiation beyond the red and violet extremes of the spectrum?

Name the radiations whose wavelength range is from 100 Å to 4000 Å (or 10 nm to 400 nm).

Name two sources of ultraviolet radiation.

How can the presence of ultraviolet radiation be detected?

Name two sources of infrared radiation.

How can the presence of infrared Radiations be detected?

State two properties of infrared radiations which differ from visible light.

State three properties of infrared radiations similar to that of visible light.

Give reason for the following:

Infrared radiations are used as signals during war.

State two properties of ultra-violet radiations which differ from visible light.

State two uses of ultraviolet radiation.

Give reason for the following:

The photographic darkrooms are provided with infrared lamps.

Give reason for the following:

Infrared radiations are used for photography in fog.

State three properties of ultra-violet radiation similar to visible light.

What do you understand by spectrum? Name the seven prominent colours in order, as obtained in the spectrum of white light.

Distinguish between an impure spectrum and a pure spectrum.

Give one use of electromagnetic radiation in Microwaves.

Give one use of electromagnetic radiation in Ultraviolet radiation.

Give one use of electromagnetic radiations in Infrared radiation.

Write the range of wavelength of the visible spectrum.

Write the range of wavelength of the ultraviolet spectrum.

Write the range of wavelength of the infrared spectrum.

Write approximate wavelength for (i) blue (ii) red light. Which colour has the higher speed in a vacuum? Which colour has the higher speed in the glass?

Suggest one way, in each case, by which we can detect the presence of Infrared radiations.

Suggest one way, in each case, by which we can detect the presence of Ultraviolet radiation.

Give one use of infrared radiations.

Name the radiations used for the detection of fracture in bones.

Name the region beyond the violet end of the spectrum called.

Name the radiation of a wavelength longer than 8 × 10⁻⁷ m.

State two uses of infrared radiations.

What effect do the ultra-violet radiations have on the human body?

Explain, why quartz prism is required for obtaining the spectrum of ultra-violet light?

Give reason for the following:

A rock salt prism is used instead of a glass prism to obtain the infrared spectrum.

Name the radiations that are used for photography at night.

A prism causes dispersion of white light while a rectangular glass block does not. Explain.

Sunlight entering through a narrow aperture falls on a prism. Draw a neat labelled ray diagram to show the formation of the spectrum on a screen. Name the colour obtained nearer the base of the prism.

In the figure, a beam of light consisting of three colours blue, red, and yellow is incident on a prism and on a rectangular glass block respectively. Complete the diagram by drawings of the refracted and emergent rays.

In the figure, a beam of light consisting of three colours blue, red, and yellow is incident on a prism and on a rectangular glass block respectively. Complete the diagram by drawings of the refracted and emergent rays.

In the diagram, a narrow beam of white light is incident on a right-angled isosceles prism. The critical angle of the material of prism for the yellow colour of white light is 45°. Complete the diagram to show the path of blue, yellow, and red colours of white light till they emerge out of the prism.

Draw a neat diagram to show the arrangement you would use to project a pure spectrum of white light on a screen.

Comment on the statement: ‘When any ray of white light is incident on a glass prism, it simply disperses it into its seven constituent colours.

An imaginary material reflects red light, scatters green light, transmits blue light, and absorbs yellow, orange, and violet light. A cube of this material is shown in the given diagram.

The surface is illuminated with a beam of white light. What colour will this cube appear?
(i) from above,
(ii) from below and
(iii) from the sides?

What is the wavelength of the wave whose frequency is 10¹² Hz? Name the electromagnetic wave.