The water in a jet propelled boat is drawn through the openings facing the direction of motion of the boat. The efficiency of propulsion is given by

A $$\frac{{2{\text{v}}}}{{{{\text{V}}_{\text{r}}} - {\text{v}}}}$$
B $$\frac{{2{\text{v}}}}{{{{\text{V}}_{\text{r}}} + {\text{v}}}}$$
C $$\frac{{\text{V}}}{{{{\text{V}}_{\text{r}}} - {\text{v}}}}$$
D $$\frac{{\text{V}}}{{{{\text{V}}_{\text{r}}} + {\text{v}}}}$$

Correct Answer: $$\frac{{2{\text{v}}}}{{{{\text{V}}_{\text{r}}} + {\text{v}}}}$$

Bissoy MCQ
#Mechanical Engineering #Hydraulics And Fluid Mechanics In ME

Related Questions

The efficiency of jet propulsion for a ship with inlet orifices at right angles to the direction of motion of ship is given by
A $$\frac{{2\left( {{{\text{V}}_{\text{r}}} - {\text{v}}} \right){\text{v}}}}{{{\text{V}}_{\text{r}}^2}}$$
B $$\frac{{2\left( {{{\text{V}}_{\text{r}}} + {\text{v}}} \right){\text{v}}}}{{{\text{V}}_{\text{r}}^2}}$$
C $$\frac{{\left( {{{\text{V}}_{\text{r}}} - {\text{v}}} \right){\text{v}}}}{{{{\text{V}}_{\text{r}}}}}$$
D $$\frac{{\left( {{{\text{V}}_{\text{r}}} + {\text{v}}} \right){\text{v}}}}{{{{\text{V}}_{\text{r}}}}}$$
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A One-half
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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 a velocity v is
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