A larger water tank open at the top has a small hole in the bottom when the water level is 30m above the bottom of the tank, the speed of the water leaking from the hole is:
Correct answer: B. 24m/s
- A. 2.5m/s
- B. 24m/s
- C. 4.44m/s
- D. Cannot be calculated unless the area of the hole is given
Explanation
Torricelli's theorem: v = √(2 g h). With g ≈ 10 m/s² and h = 30 m, v = √(2×10×30) = √600 ≈ 24.49 m/s. Area is irrelevant for efflux speed.
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