General Physics Questions And Answers


Q1. 
How much intensity of the image is increased if the diameter of the objective of a telescope is doubled?

Ans.
Four times


Q2. 
A fly is sitting on the objective of a telescope. What will be its effect on the final image of the distant object?

Ans.
Reduces


Q3. 
Two lenses of focal lengths 5 cm and 50 cm are to be used for making a telescope. Which lens will you use for the objective?

Ans.
50 cm


Q4. 
Which of the following is used to increase the range of a telescope?

Ans.
Increasing the diameter of the objective


Q5. 
The upper part of the bi-focal lens is a convex lens while its lower part is a concave lens.

Ans.
False


Q6. 
The Refractive index and wavelength are directly proportional to each other.

Ans.
False


Q7. 
How many types of spherical refracting surfaces are there?

Ans.
2


Q8. 
Which among the following is a portion of a transparent refracting medium bound by one spherical surface and the other plane surface?

Ans.
Lens


Q9. 
X is thicker in the middle than at the edges, whereas, Y is thicker at the edges than in the middle. Identify ‘X’ and ‘Y’.

Ans.
X = convex lens; Y = concave lens


Q10. 
Sign conventions for spherical refracting surface are the same as those for spherical mirrors.

Ans.
True