Question

A water tank of height $10m$, completely filled with water is placed on a level ground. It has two holes one at $3m$ and the other at $7m$ from its base. The water ejecting from:

• A. both the holes will fall at the same spot
• B. upper hole will fall farther than that from the lower hole
• C. upper hole will fall closer than that from the lower hole
• D. more information is required

Answer 1

Answer: (A)

both the holes will fall at the same spot

Let $h$ be the height of the hole.

From Bernoulli's Theorem,

$v=\sqrt{2g(10-h)}$

This is the velocity of water from a hole at height $h$ from bottom.

Thus the range of the water from the hole=$vt=\sqrt{2g(10-h)}\sqrt{\frac{2h}{g}}=2\sqrt{h(10-h)}$

Thus it is same for $h=3m$ and $h=7m.$