⚙️Mechanical Engineering MCQs
Mechanical Engineering MCQs
488 MCQs191
In an immersed body, centre of pressure is __________________?
Aat the centre of gravity
Babove the centre of gravity
Cbelow be centre of gravity
Dcould be above or below e.g. depend¬ing on density of body and liquid E. unpredictable
192
True one-dimensional flow occurs when_________________?
Athe direction and magnitude of the veiocity at all points are identical
Bthe velocity of successive fluid par-ticles, at any point, is the same at suc-cessive periods of time
Cthe magnitude and direction of the velocity do not change from point to point in the fluid
Dthe fluid particles move in plane or parallel planes and the streamline pat-terns are identical in each plane E. velocity, depth, pressure etc. change from point to point in the fluid flow
193
For similarity, in addition to models being geometrically similar to prototype, the following in both cases should also be equal____________________?
Aratio of inertial force to force due to viscosity
Bratio of inertial force to force due to gravitation
Cratio of inertial force to force due to surface tension
Dall the four ratios of inertial force to force due to viscosity, gravitation, sur-face tension, and elasticity
194
Cavitation will begin when__________________?
Athe pressure at any location reaches an absolute pressure equal to the saturated vapour pressure of the liquid
Bpressure becomes more than critical pressure
Cflow is increased
Dpressure is increased E. none of the above
195
A hydraulic press has a ram of 15 cm diameter and plunger of 1.5 cm. It is required to lift a weight of 1 tonne. The force required on plunger is equal to_________________?
A10 kg
B100 kg
C1000 kg
D1 kg E. 10,000 kg
196
Principle of similitude forms the basis of_________________?
Acomparing two identical equipments
Bdesigning models so that the result can be converted to prototypes
Ccomparing similarity between design and actual equipment
Dhydraulic designs E. performing acceptance tests
197
Cavitation is caused by_____________________?
Ahigh velocity
Bhigh pressure
Cweak material
Dlow pressure E. low viscosity
198
For pipes, turbulent flow occurs when Reynolds number is _____________________?
Aless than 2000
Bbetween 2000 and 4000
Cmore than 4000
Dless than 4000 E. none of the above
199
In order that flow takes place between two points in a pipeline, the differential pressure between these points must be more than_______________?
Africtional force
Bviscosity
Csurface friction
Dall of the above E. none of the above
200
For a body floating in a liquid the normal pressure exerted by the liquid acts at ____________________?
Abottom surface of the body
Be.g. of the body
Cmetacentre
Dall points on the surface of the body E. all of the above