Fluid Mechanics and Machinery MCQs | Page - 5

Explanation: the relative velocity of the jet is denoted as vr1. it is the relative velocity at the inlet to the vane. relative velocity of inlet to the vane is obtained by subtracting vectorially the velocity of the vane with its absolute velocity. it happens in the same way for vr2. thus, if the friction is neglected, then vr1 = vr2.

Explanation: the relative velocity of the jet is denoted as vr1. it is the relative velocity at

Explanation: through inlet orifices, which are facing the direction of motion of the ship, the water from the sea can be taken by the pump. we can also take the sea water from the pump when the inlet orifices are at right angles with respect to the motion of the ship.

Explanation: jet propulsion of ship is less efficient than screw propeller due to large amount of frictional losses developed in the pump and the pipeline. thus, it is rarely used in ships.

Explanation: a jet strikes a curved plate at its centre. force exerted by a jet on a stationery plate happens in three cases. the

Explanation: a jet engine is broadly classified into four types of jet. the four types of jet are turbojet, ramjet, scramjet, and pulse jet. there isn’t anything related to the propulsive jet and thus cannot be the answer.

Explanation: when the casing in a centrifugal pump decelerates the flow, pressure in the turbine increases. the diffuser helps this happen. the shape of the diffuser passing present in the centrifugal pump is doughnut shaped.

Explanation: the velocity imparted by the impeller is converted into pressure energy. it

Explanation: the consequence of newtons second law is the conservation of angular momentum. this, in accordance with newtons second law, provides the basic details to define parameters in the centrifugal pump.

Explanation: centrifugal pumps are used to transport fluids. they transport fluids by conversion of energies. centrifugal pumps transport fluids by converting rotational kinetic energy to hydrodynamic energy.