List of top Chemical, Thermal and Polymer Engineering Questions

A production equipment costs ₹200000. Its salvage value is ₹25000. The expected return is ₹50000 per annum. The corporate taxes are taken as 30%. The payback period will be:
For a typical project, the cumulative cash flow is zero at the:
When the interest is compounded monthly, the effective interest rate will be:
In the industrial production of nitric acid, oxidation of ammonia with air in the presence of 90% platinum, 10% rhodium catalyst in the converter constitutes the first step, the feed gas to the converter contains around:
Compared to saturated oils, unsaturated oils have:
A furnace wall of thickness 1m and surface area 2m² is made of a material whose thermal conductivity is 1 kJ/hr.m°C. The temperature of the inner surface of the wall is 1000°C and of outer surface is 200°C. Heat flow through the wall in kJ/hr will be:
The McCabe-Thiele method used to find the number of theoretical stages required in a distillation operation is based on the assumption(s) that:
Steady state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapour-gas mixture is:
For economical operation in gas absorption, the operating line approximately:
Which of the following is used as an 'entrainer' in the separation of acetic acid-water mixture by distillation?
Match LIST-I with LIST-II and select the correct answer using the codes given below the lists.\[\begin{array}{|c|c|} \hline \textbf{LIST-I} & \textbf{LIST-II} \\ \hline \text{A. Rotary atomizer} & \text{1. Kinetic energy} \\ \hline \text{B. Relative volatility} & \text{2. Centrifugal energy} \\ \hline \text{C. Pneumatic nozzle} & \text{3. Distillation} \\ \hline \text{D. Selectivity} & \text{4. Liquid-liquid extraction} \\ \hline \end{array}\] Choose the correct answer from the options given below:
The best purpose served by the baffles used in agitated vessels is to:
Baffles are provided in heat exchangers to:
A pipe with diameter 25 cm at the entrance carries oil with specific gravity 0.9 at a velocity of 3 m/s. At the exit section the diameter of the pipe is 20 cm. The velocity at the exit section is:
Match LIST-I with LIST-II and select the correct answer using the codes given below the lists.\[\begin{array}{|c|c|} \hline \textbf{LIST-I} & \textbf{LIST-II} \\ \hline \text{A. Stanton number} & \text{I. Natural convection for ideal gases} \\ \hline \text{B. Grashof number} & \text{II. Mass Transfer} \\ \hline \text{C. Peclet number} & \text{III. Forced convection} \\ \hline \text{D. Schmidt number} & \text{IV. Forced convection for small Prandtl number} \\ \hline \end{array}\] Choose the most appropriate answer from the options given below:
For steady flow and constant value of conductivity, the temperature distribution for a plane wall is:
Two rods, one of length L and the other of length 2L, are made of the same material and have the same diameter. The two ends of the longer rod are maintained at 100°C. One end of the shorter rod is maintained at 100°C while the other end is insulated. Both the rods are exposed to the same environment at 40°C. The temperature at the insulated end of the shorter rod is measured to be 55°C. The temperature at the mid point of the longer rod would be:
A rigid spherical particle is undergoing free settling in a liquid of density 750 \( \text{kg/m}^3 \), viscosity \( 9.81 \times 10^{-3} \, \text{Pa.s} \). Particle density is four times the liquid density. Taking the acceleration due to gravity as \( 9.81 \, \text{m/s}^2 \) and assuming Stokes' law is valid, the terminal settling velocity of the particle in \( \text{ms}^{-1} \) is:
In the laminar boundary layer over a flat plate, the ratio of \( \delta/x \) varies as \( Re^k \) (Where, \( Re \) is Reynolds number). The value of \( k \) is:
Match the LIST-I with LIST-II:\[\begin{array}{|c|c|} \hline \textbf{LIST-I} & \textbf{LIST-II} \\ \hline \text{A. Gauss Seidel method} & \text{I. Interpolation} \\ \hline \text{B. Forward Newton method} & \text{II. Non-linear Differential equation} \\ \hline \text{C. Runge Kutta method} & \text{III. Numerical Integration} \\ \hline \text{D. Trapezoidal rule} & \text{IV. Linear algebraic equations} \\ \hline \end{array}\] Choose the correct answer from the options given below:
For an ordinary differential equation \( y'' + y' = x^2 + 2x + 4 \), the particular integral is given by:
Bag I contains 4 red and 3 green balls and Bag II contains 3 blue and 4 green balls. One ball is drawn at random from each bag, then the probability that one of the drawn balls is red and the other is blue, is:
In a constant pressure cake filtration with an incompressible cake layer, the volume of filtrate (V) is measured as a function of time, t. The plot of \( \frac{t}{V} \) versus \( V \) gives a straight line with slope \( 10^4 \, \text{sm}^{-3} \). Filter area is \( 0.005 \, \text{m}^2 \), viscosity of filtrate is \( 10^{-3} \, \text{Pa.s} \), and the overall pressure drop across filter is \( 200 \, \text{kPa} \). What is the value of filter medium resistance in \( \text{m}^{-1} \)?
The eigen value corresponding to the eigen vector \(\begin{bmatrix} 1 \\ 2 \end{bmatrix}\) for the matrix \(\begin{bmatrix} 4 & 2 \\ 2 & 4 \end{bmatrix}\) is:
For the function \(f(x) = 2x^3 - 15x^2 + 36x + 10\), the local maxima and local minima occur respectively at: