List of top Mechanical Engineering Questions

What is the primary reason for using a key in shaft and gear assemblies?
A shaft is required to transmit a power of 25 kW at 360 rpm. The force analysis due to attached parts results in Bending Moment of 830 Nm at a section between bearings. If permissible stresses in the shaft are 60 N/mm\(^2\) in bending and 40 N/mm\(^2\) in shear, calculate the diameter of the shaft.
Heat transfer of 800 kJ occurs from a source at 500 K to surroundings at 300 K. Calculate maximum available work.
Which of the following processes is isobaric?
In a clock mechanism, hour and minute hands are connected by _________ gear train.
What is the significance of the "instantaneous center of zero velocity" in mechanism analysis?
In a project network, two parallel activities start from the same node and merge at the same succeeding node. Their durations are: Activity A = 6 days, Activity B = 9 days. Which statement is correct?
Consider a simple gas turbine (Brayton) cycle and a gas turbine with perfect regeneration. In both the cycles, the pressure ratio is 6 and the ratio of the specific heats of the working medium is 1.4. The ratio of minimum to maximum temperatures is 0.3 (with temperatures expressed in K) in the regenerative cycle. The ratio of the thermal efficiency of the simple cycle to that of the regenerative cycle is
Water (\(C_{\text{p}} = 4.18\text{ kJ/kg}\cdot\text{K}\)) at \(80^\circ\text{C}\) enters a counter-flow heat exchanger with a mass flow rate of \(0.5\text{ kg/s}\). Air (\(C_{\text{p}} = 1\text{ kJ/kg}\cdot\text{K}\)) enters at \(30^\circ\text{C}\) with a mass flow rate of \(2.09\text{ kg/s}\). If the effectiveness of the heat exchanger is 0.8, the LMTD (\(^\circ\text{C}\)) is
The Number of Transfer Units (NTU) method is primarily used to:
During heat treatment of steel, the hardness of various structures in increasing order is
The continuity equation for an incompressible fluid states that:
Which aggregate production planning strategy focuses on maintaining a stable workforce and using inventory to absorb demand fluctuations?
Fatigue failure occurs due to
The relative humidity of ambient air at \(300\text{ K}\) is \(50\%\) with a partial pressure of water vapour equal to \(P_{\text{v}}\). The saturation pressure of water at \(300\text{ K}\) is \(p_{\text{sat}}\). The correct relation for the air-water mixture is
A rod of steel of \(1\text{ cm}^{2}\) in cross-sectional area and \(100\text{ cm}\) long is subjected to an axial pull of \(20000\text{ N}\). If \(E = 20 \times 10^{6}\text{ N/cm}^{2}\), the elongation will be
If a heat exchanger has effectiveness = 1, it means:
Maximum velocity in laminar flow in a pipe is
A 50 mm diameter disc is to be punched out from a carbon steel sheet 1.0 mm thick. The diameter of the punch should be
What is the significance of availability (or exergy) in thermodynamics?
A hole of $25\text{H}_7$ is to be checked. IT7 tolerance = $0.021\text{ mm}$. Hole limits are:
In the Basic Economic Order Quantity (EOQ) model, if the holding cost per unit increases, the EOQ will:
A cantilever beam of rectangular cross section is subjected to a load W at its free end. If the depth of the beam is doubled and the load is halved, the deflection of the free end as compared to original deflection will be _______.
The Reynolds number is a ratio of:
What is the name of the surface that is generated with linear interpolation of two curves?