Concept:Torricelli's Law states that the speed of efflux of a fluid through a small hole is identical to the speed a body would acquire in falling freely from the surface of the fluid to the hole.
Formula:$$ v = \sqrt{2gh} $$
Solution:- The total height of the tank is \( 2.0 \text{ m} \). Since the hole is in the middle, the depth of the water surface to the hole is \( h = 1.0 \text{ m} \).
- Substitute the values: \( v = \sqrt{2 \times 9.8 \times 1.0} \).
- \( v = \sqrt{19.6} \).
- Since \( 4^2 = 16 \) and \( 4.5^2 = 20.25 \), \( \sqrt{19.6} \) is approximately \( 4.42 \text{ m/s} \).
Why other options are incorrect:Option D represents \( h = 2.0 \text{ m} \) (calculated incorrectly) or simply confusing the values. Option B is just the value of gravity, not a derived velocity.
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