EASY
Earn 100

Why are red coloured lights are used in traffic signals to stop the vehicles?

66.67% studentsanswered this correctly

Important Questions on Light Energy

EASY
Science>Physics>Light Energy>Prism and Dispersion

Why does rising Sun appears red in colour?

EASY
Science>Physics>Light Energy>Prism and Dispersion
What would be the colour of the sky if the earth had no atmosphere?
EASY
Science>Physics>Light Energy>Prism and Dispersion

Name the phenomenon due to which the sun appears reddish at sunset.

EASY
Science>Physics>Light Energy>Prism and Dispersion
The sky as seen from the surface of the moon appears dark because,
EASY
Science>Physics>Light Energy>Prism and Dispersion
Why is Tyndall effect shown by colloidal particles? State four instances of observing the Tyndall effect.
EASY
Science>Physics>Light Energy>Prism and Dispersion

Why does the colour of the sky appears blue?

EASY
Science>Physics>Light Energy>Prism and Dispersion
Why is red-coloured light used as universal signal for danger?
MEDIUM
Science>Physics>Light Energy>Prism and Dispersion
Draw a raw diagram of scattering of light in colloidal solution.
EASY
Science>Physics>Light Energy>Prism and Dispersion
Draw a labelled diagram to show (i) reddish appearance of the sun at the sunrise or the sunset and (ii) white appearance of the sun at noon when it is overhead.
MEDIUM
Science>Physics>Light Energy>Prism and Dispersion
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.
MEDIUM
Science>Physics>Light Energy>Prism and Dispersion
What happens if dispersion and scattering of light do not occur?
MEDIUM
Science>Physics>Light Energy>Prism and Dispersion
What happens when a beam of light is passed through a colloidal solution?
MEDIUM
Science>Physics>Light Energy>Prism and Dispersion

Why does the earth's sky appear blue during the daytime?

EASY
Science>Physics>Light Energy>Prism and Dispersion
 What is Tyndall effect?
EASY
Science>Physics>Light Energy>Prism and Dispersion
Why is the colour of clear sky blue?
HARD
Science>Physics>Light Energy>Prism and Dispersion
What is the reason for the blue colour of the sky? How do you appreciate the role of molecules in the atmosphere in this regard?
EASY
Science>Physics>Light Energy>Prism and Dispersion
Why is the colour of clear sky blue?
HARD
Science>Physics>Light Energy>Prism and Dispersion
Why does the sun appear reddish early in the morning? Draw the ray diagram of an arrangement for observing scattering of light in colloidal solution.
EASY
Science>Physics>Light Energy>Prism and Dispersion
Why does the sun appear reddish early in the morning ? Will this phenomenon be observed by an astronaut on the Moon ? Give reason to justify your answer. 
EASY
Science>Physics>Light Energy>Prism and Dispersion
During sunset or sunrise the sun appears reddish because: