Q. Anshul filled a large-sized tank with water and floated a big bowl in it. After that he began to drop zinc balls in the bowl one at a time. With each ball the bowl began to sink slowly. After 30 balls 3/4th of the bowl was immersed in water.
At this stage he marked the water level of the tank by putting a mark there. Meanwhile Vikas, his naughty little brother came and pressed the bowl with his hand, as a result of which the bowl sank completely into the water with the 30 zinc balls in it.
Was there any change in the water level which Anshul had marked? If so, how? If no, Why? You have to explain the above with reason.
A. Water level will be reduced. While the bowl containing balls was floating, it had raised water level in proportion to its weight and size. After it immersed in water, it displaced water according to its volume. Water affected by weight is more than the water displaced by volume (otherwise the bowl and balls would not have sunk). Therefore, water level is reduced.