Water is flowing continuously from a tap having an internal diameter 8 × 10^-3 m . The water velocity as it leaves the tap is 0.4 ms^-1 . The diameter - Physics MCQ FIITJEE AIEEE 2011 (Set Q) 2026 | ExamTest.live

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Water is flowing continuously from a tap having an internal diameter 8 \times 1 0^{- 3} m . The water velocity as it leaves the tap is 0.4 ms^{- 1} . The diameter of the water stream at a distance 2 \times 1 0^{- 1} m below the tap is close to:

Solution & Step-by-step Explanation

1. Find velocity at distance h = 0.2 m : v^{2} = u^{2} + 2 g h = (0.4)^{2} + 2 (9.8) (0.2) = 0.16 + 3.92 = 4.08 v \approx 4.08 \approx 2.02 m/s 2. Equation of continuity: A_{1} v_{1} = A_{2} v_{2} $ \frac{π d _{1}^{2}}{4} v_{1} = \frac{π d _{2}^{2}}{4} v_{2} ⟹ d_{1}^{2} v_{1} = d_{2}^{2} v_{2} $ (8 \times 1 0^{- 3})^{2} \times 0.4 = d_{2}^{2} \times 2.02 64 \times 1 0^{- 6} \times 0.4 = d_{2}^{2} \times 2.02 d_{2}^{2} \approx \frac{25.6 \times 1 0 ^{- 6}}{2.02} \approx 12.67 \times 1 0^{- 6} d_{2} \approx 3.56 \times 1 0^{- 3} m

Try it yourself before checking the explanation above.

Water is flowing continuously from a tap having an internal diameter 8 \times 1 0^{- 3} m . The water velocity as it leaves the tap is 0.4 ms^{- 1} . The diameter of the water stream at a distance 2 \times 1 0^{- 1} m below the tap is close to:

7.5 \times 1 0^{- 3} m

9.6 \times 1 0^{- 3} m

3.6 \times 1 0^{- 3} m

5.0 \times 1 0^{- 3} m

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