Question

A boy carries a fish in one hand and a bucket (not full) of water in the other hand. If he places the fish in the bucket, the weight now carried by him (assume that water does not spill)
A. is less than before
B. is more than before
C. is the same as before
D. depends upon his speed.

Answer 1

Hint: The above problem can be resolved by using the concepts of Buoyancy and fundamentals of the buoyant force. As the buoyant force has its significance in determining the apparent weight of the body being fully submerged as well as partially submerged. Moreover, Buoyancy has its vital applications in determining the metacentre of the body.

 Complete step by step answer:
Given: The boy carrying the fish in one hand and a bucket of water in the other hand.
The boy holding the fish in one hand, while the bucket full of water on the other hand creates some system of forces to be acting between the water in the bucket and the fish. The water in the bucket applies some magnitude of buoyant force on the fish, that is exactly equivalent and is opposite to the force applied by the fish on water. Due to this, both forces cancel out their effect, resulting in no variation in the weight carried by the boy.
Therefore, the weight carried by the boy will remain same as before
So, the correct answer is “Option C”.

Note:
The problem involves determining the change in weight for the submerged body in water. This accounts for the involvement of fundamental concepts of Buoyant force as well as the phenomena known as Buoyancy. Moreover, the balancing of forces is also important to predict the apparent weight of the object being submerged underneath the water.