Blue Sky

Q.

Question 23
Why is the colour of the clear sky blue?

Q. Assertion(A): The sky appear dark instead of blue to an astronaut.

Reason(R) : Scattering of sunlight cannot happen due absence of atmosphere in outer space.

1. (A) is true but (R) is false.
2. (A) is false but (R) is true.
3. Both (A) and (R) are true and (R) is correct explanation of (A).
4. Both (A) and (R) are true and (R) is not correct explanation of (A).

Q.

How is light scattered by the air?

Q.

Lets say if there was no atmosphere on the earth, would scattering of light happen even then?

Q.

Why clouds appear black during or before rain?

Q. Assertion (A): The sky appears dark instead of blue to an astronaut.
Reason (R): Scattering of sunlight cannot happen due to the absence of atmosphere in outer space.
Choose the correct option.

1. Both A and R are true and R is the correct explanation of A
   
2. Both A and R are true but R is not the correct explanation of A
   
3. A is true but R is false
   
4. A is false but R is true
   

Q. This section contains 1 Assertion-Reason type question, which has 4 choices (a), (b), (c) and (d) out of which ONLY ONE is correct.

इस खण्ड में 1 कथन-कारण प्रकार का प्रश्न है, जिसमें 4 विकल्प (a), (b), (c) तथा (d) दिये गये हैं, जिनमें से केवल एक सही है।


A : The sky appears blue due to atmospheric refraction.
A : वायुमण्डलीय अपवर्तन के कारण आकाश का रंग नीला दिखाई देता है।

R : The sky appears dark instead of blue to an astronaut in space.
R : अन्तरिक्ष में अन्तरिक्षयात्री को आकाश नीले की बजाय काला दिखाई देता है।

1. Both (A) and (R) are true and (R) is the correct explanation of (A)
   
   (A) तथा (R) दोनों सही हैं तथा (R), (A) का सही स्पष्टीकरण है
2. Both (A) and (R) are true but (R) is not the correct explanation of (A)
   
   (A) तथा (R) दोनों सही हैं लेकिन (R), (A) का सही स्पष्टीकरण नहीं है
3. (A) is true but (R) is false
   
   (A) सही है लेकिन (R) गलत है
4. (A) is false but (R) is true
   
   (A) गलत है लेकिन (R) सही है

Q.

why does sky look orange when the sun rises or sets?

Q. Assertion(A): The sky appear dark instead of blue to an astronaut.

Reason(R) : Scattering of sunlight cannot happen due absence of atmosphere in outer space.

1. Both (A) and (R) are true and (R) is correct explanation of (A).
2. Both (A) and (R) are true and (R) is not correct explanation of (A).
3. (A) is true but (R) is false.
4. (A) is false but (R) is true.

Q.

why sky is blue?

Q. Assertion (A): The sky appears dark instead of blue to an astronaut.
Reason (R): Scattering of sunlight cannot happen due to the absence of atmosphere in outer space.

1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. (A) is false but (R) is true.

Q. Had the atmosphere not been present, what would be the appearance of sky? [2 MARKS]

Q. Assertion (A): The sky appears dark instead of blue to an astronaut.
Reason (R): Scattering of sunlight cannot happen due to the absence of atmosphere in outer space.

1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. (A) is false but (R) is true.

Q. Statement-1:
On viewing the deer blue portion of the sky through a Calcite Crystal, the intensity of transmitted light varies as the crystal is rotated.
Statement-2:
The light coming from the sky is polarized due to scattering of sun light by particles in the atmosphere. The scattering is largest for blue light.

1. Statement-1 is true, statement-2 is true; statement-2 is not correct explanation of statement-1.
2. Statement -1 is false, statement -2 is true.
3. Statement-1 is true, statement-2 is false
4. Statement-1 is true, statement-2 true; statement-2, is the correct explanation of statement-1

Q.

Why do clouds appear white while sky appears blue?

1. Clouds don't scatter light.

2. Clouds scatter only blue light.

3. Clouds scatter all colours of light.

4. Clouds scatter only red light.

Q. Which is responsible for the blue colour of the sky?

1. Refraction
2. Scattering
3. Dispersion
4. Diffraction

Q.

Why do clouds appear white while sky appears blue?

1. Clouds don't scatter light.

2. Clouds scatter only blue light.

3. Clouds scatter all colours of light.

4. Clouds scatter only red light.

Q.

Question 13
Why does the sky appear dark instead of blue to an astronaut?

Q. Instead of all 7 colours (violet, indigo, blue, green, yellow, orange, red) if the sun only emits green, yellow, orange and red, what would be the possible colour of the sky?

1. Blue
2. Red
3. Green
4. Black

Q. Which is responsible for the blue colour of the sky?

1. Scattering
2. Dispersion
3. Diffraction
4. Refraction

Q.

Let's say if there was no atmosphere on the earth, would scattering of light happen even then?

Q. The sky would have appeared ________ in colour if Earth didn’t have the atmosphere.

1. yellow
2. red
3. black
4. blue