List of top Mechanical Engineering Questions

In transient heat conduction, the two significant dimensionless numbers are
The ratio of the energy transferred by convection to that by conduction is represented by
In an enclosure there are 8 surfaces. How many individual radiation view factors are involved?
Which two properties are sufficient to define the state point of moist air?
In the heat flow equation, \( Q = -kA \frac{\Delta T}{L} \), the expression for thermal resistance is given by (k - thermal conductivity, A - Area of cross section, L - thickness of the wall)
If the radius of a current carrying wire is less than the critical radius, then the addition of electrical insulation will enable the wire to carry a higher current because:

A process is described by 1-2-3 on a Psychrometric chart. Name the process in the same sequence.

A fin of length \( L \) is applied the boundary conditions associated with a very long fin, the adiabatic tip fin, and the finite convective tip fin, which of the following observation about the fin-tip temperature (\( T \)) for these three cases is correct.
The air standard cycle involving constant pressure heat addition and constant volume heat rejection corresponds to
Carnot cycle is different from Rankine cycle in steam power plant during the following process.
Which of the following equation is the basis for the construction of Mollier diagram? (P- Pressure, V- Volume, T- Temperature, U- Internal Energy, h - Enthalpy, s - Entropy)
What is the effect of involving Reheat and Regenerative cycle individually on cycle efficiency in the same sequence?
A pure substance is a substance of constant composition throughout its mass and follows
The efficiency of Brayton cycle corresponding to maximum net work obtained for \( T_{\text{max}} = 900 \, \text{K} \) and \( T_{\text{min}} = 400 \, \text{K} \) is given by
A thermodynamic cycle is impossible if

The cycle shown in Figure is composed of internally reversible processes on a T-S diagram. Which of the following is the expression for thermal efficiency in terms of the temperatures?

A heat engine is supplied with 250 kJ/s of heat at a constant temperature of 227°C; the heat is rejected at 27°C. If the cycle is reversible, then the amount of heat rejected is:
Sommerfeld number consists of parameters
Joule’s experiment states that for a cyclic process
During one cycle the working fluid in an engine engages in two work interactions: 15 kJ to the fluid and 45 kJ from the fluid, and three heat interactions, two of which are known: 75 kJ to the fluid and 40 kJ from the fluid. The magnitude and direction of the third heat transfer is
Heat Engine cycle represents the devices Boiler (B), Condenser (C), Pump (P) and Turbine (T) arranged in the sequence of:
An ideal gas at \( 27^\circ C \) is heated at constant pressure till the volume becomes three times. The temperature of the gas will be
Which of the following is not an extensive property?
In the multiple disc clutch, if there are six discs on the driving shaft and five discs on the driven shaft, then the number of pairs of contact surfaces will be
An element is subjected to a tensile stress of 60 MPa and a shear stress of 40 MPa. If the material has the yield strength obtained in a simple tensile test is 320 MPa, the factor of safety based on maximum principal stress theory is