A man is sitting in a boat which is floating in a pond. If the man drinks some water from the pond, water level in the pond decreases.
Correct answer: (a)
When a man drinks water from the pond, the water level of pond will decrease., but as the weight of boat, man increases because due to the addition of water to the boat, the level of pond will increase.
Hence, the two parts cancel each other's effect finally resulting in no change.