Fluid Mechanics (Set 5) | Multiple Choice Questions

1. The surface tension of mercury at normal temperature compared to that of water is

More

Less

Same

More or less depending on size of glass tube

2. An air vessel is provided at the summit in a siphon to

Avoid interruption in the flow

Increase discharge

Increase velocity

Maintain pressure difference

3. The unit of viscosity is

Metres² per sec

kg-sec/metre

Newton-sec per metre²

Newton-sec per meter

4. Select the correct statement

Weber's number is the ratio of inertia force to elastic force.

Weber's number is the ratio of gravity force to surface tension force.

Weber's number is the ratio of viscous force to pressure force.

Weber's number is the ratio of inertia force to surface tension force.

5. Choose the wrong statement. Alcohol is used in manometer, because

Its vapour pressure is low

It provides suitable meniscus for the inclined tube

Its density is less

It provides longer length for a given pressure difference

6. When a tank containing liquid moves with an acceleration in the horizontal direction, then the free surface of the liquid

Remains horizontal

Becomes curved

Falls on the front end

Falls on the back end

7. A pressure of 25 m of head of water is equal to

25 kN/ m²

245 kN/ m²

2500 kN/m²

2.5 kN/ m²

8. The hammer blow in pipes occurs when

There is excessive leakage in the pipe

The pipe bursts under high pressure of fluid

The flow of fluid through the pipe is suddenly brought to rest by closing of the valve

The flow of fluid through the pipe is gradually brought to rest by closing of the valve

9. The resultant upward pressure of the fluid on an immersed body is called

Up-thrust

Buoyancy

Center of pressure

All the above are correct

10. When the water level on the downstream side of a weir is above the top surface of a weir, the weir is known as

Narrow-crested weir

Broad-crested weir

Ogee weir

Submerged weir