A vertical circular jet of liquid strikes a conical deflector having a mass m. The deflector is centered

at the jet centerline and is supported by the fluid flow only. The entering jet has a diameter D. The

magnitude of liquid velocity at the upper edge of the deflector equals to the entering velocity U.

The liquid has a constant density p, and the flow can be considered inviscid. Derive an expression

for the deflector angle a that is required for the jet to be able to balance the deflector weight.

Express your answer in terms of m, U, D, p, and g.

α

↑U

Figure 2: Sketch for Problem

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U