set 4 MCQ Questions & Answers Detailed Explanation

Question : 1

Consider the following statements.

1. If a person looks at a coin which is in a bucket of water, the coin will appear to be closer than it really is.
2. If a person underwater looks at a coin above the water surface, the coin will appear to be at a higher level than it really is.

a) Only 2

b) Only 1

c) 1 and 2

d) Neither 1 nor 2

Question : 2

Assertion (A):
Steam is more harmful for human body than the boiling water in case of burn.
Reason (R) :
Boiling water contains more heat than steam.

a) Both A and R are true, but R is not the correct explanation of A

b) Both A and R are true and R is the correct explanation of A

c) A is true, but R is false

d) A is false, but R is true

Question : 3

An astronaut sees the colour of the sky as

a) Black

b) White

c) Blue

d) Red

Question : 4

Consider the following statements about ultrasonic waves.

1. They can destroy insects.
2. They can clean clothes by removing dust.
3. They can be used to treat diseases.
4. They can control automatic doors.

a) 3 and 4 are correct

b) 1, 2 and 3 are correct

c) 1 and 2 are correct

d) All are correct

Question : 5

In the visible spectrum the colour having the shortest wavelength is

a) violet

b) green

c) red

d) blue

Question : 6

Which one of the following statement is not true for a person suffering from hypermetropia?

a) The image of the close objects is focused behind the retina

b) The focal length of the lens is large

c) The person can see far objects distinctly

d) A concave lens is used to correct this defect