When a body is dropped in water, it's weight acts on the water and the water's upthrust acts on the body. But according to the Third Law of Motion, Both the forces must be equal and opposite. If the Third Law of Motion holds, the body must neither float nor sink ( because both forces cancel ) and stay in the middle. Please check whether the statement is true and give an appropriate explanation.
As per the third law, the two forces act on different objects, so they do not cancel each other if any particular object is your system.
When a body is in water (partially/fully), there are two forces acting on the body. One is mg by the earth and the other is buoyant force by the water. If mg > B, the body should come down. If mg = B, the body should float at the same position. If B > mg, the body should come up.
Thank You SIR!