Question

While standing on the deck of a ship, Emma observed that the reflection of a cloud was about $102\text{m}$ below the water. If the ship’s deck was $2.5\text{m}$ above the water, calculate the distance between Emma and the cloud.

• A. $101.5\text{m}$
• B. $100.5\text{m}$
• C. $99.5\text{m}$
• D. $102.5\text{m}$

Answer 1

The correct option is C $99.5\text{m}$

Given:
Image distance of cloud below the water surface $=102\text{m}$
So as per characteristic of image formed by a plane mirror, the cloud must lie at a height of $102\text{m}$ above the water surface.
Height of deck of ship above the water surface $=2.5\text{m}$

So, distance between Emma (standing on deck) and the cloud in the sky will be $=102-2.5=99.5\text{m}$