Test: Pressure & Its Measurements, Reciprocating Pumps, Flow Around Submerged Bodies - Drag & Lift - 1 - Mechanical Engineering MCQ

For pumping molasses, it is preferable to employ  

Air vessel is used in a reciprocating pump to obtain 

If a reciprocating pump having a mechanical efficiency of 80% delivers water at the rate of 80 kg/s with a head of 30 m, the brake power of thepump is: 

Match List-I (Type of pumps) with List-II (Associated features) and select the correct answer using the codes given below the Lists:

Whenever a plate is submerged at an angle with the direction of flow ofliquid, it is subjected to some pressure. What is the component of thispressure in the direction of flow of liquid, known as?  

The drag force exerted by a fluid on a body immersed in the fluid is dueto: 

Which one of the following causes lift on an immersed body in a fluidstream? 

Match List-I with List-II and select the correct answer:

Direction of flow, drag force is essentially a function of the Reynoldsnumber of the flow. 
Reason (R): As Reynolds Number is about 100 and above, eddies formedbreak away from either side in periodic fashion, forming a meanderingstreet called the Karman Vortex street.

When pressure drag over a body is large as compared to the friction drag, then the shape of the body is that of: 

The critical value of Mach number for a subsonic airfoil is associatedwith sharp increase in drag due to local shock formation and itsinteraction with the boundary layer. A typical value of this criticalMach number is of the order of: 

Assertion (A): A body with large curvature causes a larger pressure drag and, therefore, larger resistance to motion.  
Reason (R): Large curvature diverges the stream lines, decreases the velocity resulting in the increase in pressure and development of adverse pressure gradient leading to reverse flow near the boundary.

Consider the following coefficients: (R_e = Reynolds number)
1. 1.328 R_{e_ (0.5)} for laminar flow
2. 2.072 R_{e_ (0.2)} for turbulent flow
3. 0.072 R_{e _ (0.2)} for turbulent flow
4. 1.028 R_{e _ (0.5)} for laminar flow
The coefficient of drag for a flat would include

The Magnus effect is defined as 

An automobile moving at a velocity of 40 km/hr is experiencing a wind resistance of 2 kN. If the automobile is moving at a velocity of 50 km/hr,the power required to overcome the wind resistance is:  

Improved streaming produces 25% reduction in the drag coefficient of a torpedo. When it is travelling fully submerged and assuming the driving power to remain the same, the crease in speed will be:

A parachutist has a mass of 90 kg and a projected frontal area of 0.30m² in free fall. The drag coefficient based on frontal area is found to be 0.75. If the air density is 1.28 kg/m³, the terminal velocity of the parachutist will be: