Making a Plane Mirror

Q.

Question 20 (e)

Boojho planned an activity to observe an object A through pipes as shown in figure, so that he could see objects which he could not directly see. At each corner a plane mirror is placed at 45 degrees in order to deviate the light rays by 90 degrees.



If any of the mirrors is removed, will he be able to see the objects?

Q. Mirrors are surfaces which reflect light irregularly.

1. True
2. False

Q. 82. The separation between the screen and a plane mirror is 2r. An isotropic point source of light is placed exactly midway between the mirror and the screen. Assume that mirror reflects 100% of incident light. Then the ratio of illuminances on the screen with and without the mirror is A) 10 : 1 B) 2 : 1 C) 10 : 9 D) 9 : 1

Q. Two plane mirrors A and B are placed parallel to each other at a separation of $40\text{cm}$. An object is placed at a distance of $10\text{cm}$ from mirror A. What will be the distance between the images of the object formed by the mirrors?

1. $60\text{cm}$
2. $20\text{cm}$
3. $100\text{cm}$
4. $80\text{cm}$

Q. The Braille system assists blind people only to read.

1. True
2. False

Q. People with hypermetropia can see distant objects clearly.

1. False
2. True

Q. Which component of the mirror reflects the light?

1. Opaque paint at the back
2. Front side of glass
3. Silver polishing
4. Back side of glass

Q. The image formed at retina by eyelens is a virtual image.

1. False
2. True

Q. Which of the following are internal parts of a human eye?

1. Iris
2. Eyelids
3. Pupil
4. Cornea
5. Eye lashes
6. Retina
7. Ciliary muscles
8. Vitreous humour