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Let's discuss a problem based on the maximum height of water in a tank with a hole. Try the problem yourself first and then read the solution.

**The Problem: Maximum Height of Water**

A large tank is filled with water of (70 cm^3/s). A hole of cross-section (0.25cm^2) is punched at the bottom of the tank. Find the maximum height to which the tank can be filled.

**Solution:**

For the water level to remain stationary volume efflux= rate of filling = (x)

The velocity $$ v=\sqrt{2gh}$$ where (g) is the acceleration due to gravity.

Hence,$$ vA=\sqrt{2gh}A$$ $$ =x$$ $$=70cm^3//s$$

The maximum height $$ h=\frac{x^2}{2gA^2}$$ $$=\frac{70^2}{2\times 980\times(0.25)^2}$$ $$=40cm$$

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Um could you explain why the height is Maximum when the volume flow rates become equal. If the speed of outflow is lesser then wouldn't the height increase more?