**
The force exerted (in newton) by a jet of water impinging normally on a fixed plate is**

**(A)**$\frac{\rho aV}{2}$

**(B)**$\rho aV$

**(C)**$\frac{\rho a{V}^{2}}{2}$

**(D)**$\rho a{V}^{2}$

**D**

**
The force exerted by a jet of water (in a direction normal to flow) impinging on a fixed plate inclined at an angle θ with the jet is**

**(A)**$\frac{\rho aV}{2}\times \mathrm{sin}\theta $

**(B)**$\rho aV\times \mathrm{sin}\theta $

**(C)**$\frac{\rho a{V}^{2}}{2}\times \mathrm{sin}2\theta $

**(D)**$\rho a{V}^{2}\times \mathrm{sin}\theta $

**C**

**
The force exerted by a jet of water impinging normally on a plate which due to the impact of jet, moves in the direction of jet with velocity u is**

**(A)**$\frac{{\displaystyle \rho a\left(V-u\right)}}{2}$

**(B)**$\rho a\left(V-u\right)$

**(C)**$\frac{{\displaystyle \rho a{\left(V-u\right)}^{2}}}{2}$

**(D)**$\rho a{\left(V-u\right)}^{2}$

**D**

**
The ration of the normal force of a jet of water on a plane inclined at an angle of 30° as compared to that when the plate is normal to jet, is**

**(A)**$\frac{1}{\sqrt{2}}$

**(B)**$\frac{1}{2}$

**(C)**$1$

**(D)**$\sqrt{2}$

**B**

**
A jet of water is striking at the centre of a curved vane moving with a uniform velocity in the direction of the jet. For the maximum efficiency, the vane velocity is …………. of the jet velocity.**

**(A)**one-half

**(B)**one-third

**(C)**two-third

**(D)**three-fourth

**B**