Question

There is a fire in the building which is started from its rooftop and is rapidly growing. Assuming that the water projected from hose behaves as a projectile, how far from that building should the fire hose be located to hit the highest possible height that it can hit. Given hose pipe is adjusted such that water leaves at a fixed angle with the horizontal at speed u m/s?

• A.
• B.
• C.
• D.

Answer 1

The correct option is B

As angle of projection is fixed,
So, we have to adjust x, such that when water reaches building it is at its topmost point, which comes at half of the range of projectile.
Hence, x = $\frac{R}{2}$ = $\frac{u^{2}sin2\theta }{2g}$.