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Statement-1: A fast jet of water from a hose spreads out like a fountain when the hose is pointed vertically upward, but it narrows down when pointed vertically downward. Statement-2: For the steady flow of an incompressible fluid, the volume flow rate stays constant along the stream. Select the correct option.

1. Statement-1 is True, Statement-2 is True; Statement-2 is the correct explanation of Statement-1.
2. Statement-1 is True, Statement-2 is True; Statement-2 is NOT the correct explanation of Statement-1.
3. Statement-1 is True, Statement-2 is False.
4. Statement-1 is False, Statement-2 is True.

Correct answer: Statement-1 is True, Statement-2 is True; Statement-2 is the correct explanation of Statement-1.

Solution

Going upward, gravity decelerates the water so its speed v decreases; by continuity (A*v = const) the cross-section A increases, so the stream widens/spreads. Going downward, gravity accelerates the water so v increases and A decreases, so the stream narrows. Thus Statement-1 is true, and the continuity equation of Statement-2 is exactly the reason for it, so Statement-2 correctly explains Statement-1.

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