Mass M slides in a frictionless slot in the horizontal direction and the bob of mass m is hinged to mass M at C, through a rigid mass less rod. This system is released from rest with 0 =30°. At the instant when 0 = 0, the velocities of m and M can be determined using the fact that, for the system (i.e., m and M together),

1.  the linear momentum in x and y directions are conserved but the energy is not conserved

2.  the linear momentum in x and y directions are conserved and the energy is also conserved

3.  the linear momentum in x direction is conserved and the energy is also conserved

4.  the linear momentum in y direction is conserved and the energy is also conserved

4

the linear momentum in x direction is conserved and the energy is also conserved

Explanation :
No Explanation available for this question

A cyclic heat engine does 50 kJ of work per cycle. If the efficiency of the heat engine is 75%, the heat rejected per cycle is

1.  16(2/3)k  J.

2.  33(1/3) kJ

3.  37(1/2) kJ

4.  66(2/3)kJ

4

16(2/3)k  J.

Explanation :
No Explanation available for this question

A single-acting two-stage compressor with complete inter cooling delivers air at 16 bar. Assuming an intake state of 1 bar at 15°C, the pressure ratio per stage is

1.  16

2.  8

3.  4

4.  2

4

4

Explanation :
No Explanation available for this question

The horizontal and vertical hydrostatic forces Fx and Fy on the semi-circular gate, having a width co into the plane of figure, are

1.  Fx=ρghr and Fy=0

2.  Fx=2ρghr ω and Fy=0

3.  Fx=ρghrω and Fy=ρgωr2/2

4.  Fx=2ρghrω and Fy=πρgωr2/2

4

Fx=2ρghrω and Fy=πρgωr2/2

Explanation :
No Explanation available for this question

1.  Compressible and irrotational

2.  Compressible and not irrotational

3.  Incompressible and irrotational

4.   Incompressible and not irrotational

4

Incompressible and not irrotational

Explanation :
No Explanation available for this question

A small steam whistle (perfectly insulated and doing no shaft work) causes a dropof 0.8 kJ/kg in the enthalpy of steam from entry to exit. If the kinetic energy of the steam at entry is negligible, the velocity of the steam at exit is

1.  4 m/s

2.  40 m/s

3.  80 m/s

4.  120 m/s

4

40 m/s

Explanation :
No Explanation available for this question

For air at a given temperature, as the relative humidity is increased isothermally,

1.    The wet bulb temperature and specific enthalpy increase

2.    The wet bulb temperature increases and specific enthalpy decreases

3.  he wet bulb temperature decreases and specific enthalpy increases

4.  none

4

none

Explanation :
No Explanation available for this question

Water (Prandtl number = 6) flows over a flat plate which is heated over the entire length. Which one of the following relationship between the hydrodynamic boundary layer thickness (δ) and the thermal boundary layer thickness (δt) is true

1.  8t > 8

2.  8t < 8

3.  8t = 8

4.  Cannot be predicted

4

8t < 8

Explanation :
No Explanation available for this question

In a spark ignition engine working on the ideal Otto cycle, the compression ratio is 5.5. The work output per cycle (i.e., area of the P-V diagram) is equal to 23.625x105xVcJ, where Vc is the clearance volume in m3. The indicated mean effective pressure is

1.  4.295 bar

2.  5.250 bar

3.  86.870 bar

4.  106.300 bar

4

5.250 bar

Explanation :
No Explanation available for this question

1.  2.67

2.  8.45

3.  26.72

4.  84.50

4