Question

The image formed by a periscope is __________. ​

• A. real and laterally inverted​
• B. virtual and laterally inverted​
• C. virtual but not laterally inverted​
• D. real but not laterally inverted​

Answer 1

The correct option is C virtual but not laterally inverted​


Periscope is an instrument in which plane mirrors are set parallel to each other.
An image formed by the first plane mirror is virtual and lateral inverted. This reflected ray from the first mirror now can be treated as an incident ray for the second mirror.
The laterally inverted image which acts as an object for the second mirror, again gets laterally inverted from the second mirror.
When the inversion takes place twice, the second image looks the same as that of the object (and not laterally inverted).

However, the image still remains virtual. This is because a plane mirror always forms a virtual image no matter after how many reflections the incident rays are falling on it.