# Recent questions

Rajiv Gandhi Khel Ratna Award was conferred ______ Mary Kom, a six-time world champion in boxing, recently in a ceremony _____ the Rashtrapati Bhawan (the President’s official residence) in New Delhi. with, at on, in on, at to, at
Despite a string of poor performances, the chances of K.L. Rahul’s selection in the team are ________ slim bright obvious uncertain
Select the word that fits the analogy: Cover : Uncover :: Associate : _______ Unassociate Inassociate Misassociate Dissociate
Hit by floods, the kharif (summer sown) crops in various parts of the country have been affected. Officials believe that the loss in production of the kharif crops can be recovered in the output of the rabi (winter sown) crops so that the country can achieve its ... target cannot be met due to floods. Officials hope that the food-grain production target will be met due to a good rabi produce.
The difference between the sum of the first $2n$ natural numbers and the sum of the first $n$ odd numbers is ______ $n^2-n$ $n^2+n$ $2n^2-n$ $2n^2+n$
Repo rate is the rate at which Reserve Bank of India (RBI) lends commercial banks, and reverse repo rate is the rate at which RBI borrows money from commercial banks. Which of the following can be inferred from the above passage? Decrease in repo ... borrowing and decrease lending by commercial banks. Decrease in repo rate will decrease cost of borrowing and increase lending by commercial banks.
$P,Q,R,S,T,U,V,$ and $W$ are seated around a circular table. $S$ is seated opposite to $W$ $U$ is seated at the second place to the right of $R$ $P$ is not seated opposite to $Q$ $R$ is the left neighbour of $S$ Which of the following must be true? $P$ is a neighbour of $R$ $Q$ is a neighbour of $R$ $P$ is not seated opposite to $Q$ $R$ is the left neighbour of $S$
The distance between Delhi and Agra is $233$ km. A car $P$ started travelling from Delhi to Agra and another car $Q$ started from Agra to Delhi along the same road $1$ hour after the car $P$ started. The two cars crossed each other $75$ minutes after the car $Q$ started. Both ... car $Q$. How many kilometers the car $Q$ had travelled when the cars crossed each other? $66.6$ $75.2$ $88.2$ $116.5$
For a matrix $M=[m_{ij}]; \: i,j=1,2,3,4$, the diagonal elements are all zero and $m_{ij}=-m_{ji}$. The minimum number of elements required to fully specify the matrix is ________ $0$ $6$ $12$ $16$
The profit shares of two companies $P$ and $Q$ are shown in the figure. If the two companies have invested a fixed and equal amount every year, then the ratio of the total revenue of company $P$ to the revenue of company $Q$, during $2013-2018$ is ________. $15 : 17$ $16 : 17$ $17 : 15$ $17 : 16$
An irreversible gas phase reaction $2 \textbf{P} \rightarrow 4 \textbf{Q} + \textbf{R}$ is conducted in an isothermal and isobaric batch reactor. Assume ideal gas behavior. The feed is an equimolar mixture of the reactant $\textbf{P}$ and an inert gas. After complete conversion of $\textbf{P}$, the fractional change in volume is ________ (round off to $2$ decimal places).
Consider two Carnot engines $C_1$ and $C_2$ as shown in the figure. The efficiencies of the engines $C_1$ and $C_2$ are $0.40$ and $0.35$, respectively. If the temperature of Reservoir $R_1$ is $800 \: K$, then the temperature (in $K$) of Reservoir $R_3$ is ________ (round off to nearest integer).
Consider the following closed loop system with $G_p$ and $G_c$ as the transfer functions of the process and the controller, respectively. For a unit step change in the set point $(y_{sp}$), the change in the value of the response $(y)$ at steady state is _______ (round off to $1$ decimal place).
The decomposition of acetaldehyde $(X)$ to methane and carbon monoxide follows four-step free radical mechanism. The overall rate of decomposition of $X$ is $-r_X=k_2 \bigg( \dfrac{k_1}{2k_3} \bigg) ^{1/2} C_X^{3/2} =k_{\text{overall}}C_X^{3/2}$ where $k_1, k_2$ ... $k_{\text{overall}}$. The activation energy for the overall reaction (in $kJ \: mol^{-1}$) is _______ (round off to nearest integer).
Sum of the eigenvalues of the matrix $\begin{bmatrix} 2 & 4 & 6 \\ 3 & 5 & 9 \\ 12 & 1 & 7 \end{bmatrix}$ is ______ (round off to nearest integer).
In a box, there are $5$ green balls and $10$ blue balls. A person picks $6$ balls randomly. The probability that the person has picked $4$ green balls and $2$ blue balls is $\dfrac{42}{1001}\\$ $\dfrac{45}{1001}\\$ $\dfrac{240}{1001} \\$ $\dfrac{420}{1001}$
The maximum value of the function $f(x)=-\dfrac{5}{3} x^3 +10x^2-15x+16$ in the interval $(0.5,3.5)$ is $0$ $8$ $16$ $48$
$SO_2$ from air is absorbed by pure water in a counter current packed column operating at constant pressure. The compositions and the flow rates of the streams are shown in the figure. In addition, use the following data and assumptions Column operates under isothermal conditions At the operating ... of water evaporates The number of transfer units (NTU) for this column is $0.5$ $1.0$ $1.5$ $2.0$
Two film theory applies for absorption of a solute from a gas mixture into a liquid solvent. The interfacial mass transfer coefficient (in $mol \: m^{-2} \: s^{-1}$) for the gas side is $0.1$ and for the liquid side is $3$ ... . The ratio of the mass transfer resistance in the liquid film to the overall resistance is $0.0161$ $0.0322$ $0.0625$ $0.0645$
Consider the equilibrium data for methanol-water system at $1$ bar given in the future below. A distillation column operating at $1.0$ bar is required to produce $92 \: mol \: \%$ methanol. The feed is a saturated liquid. It is an equimolar mixture of methanol and water. The minimum reflux ratio is $0.33$ $0.50$ $0.54$ $1.17$
Consider the gas phase reaction $N_2O_4 \rightleftarrows 2NO_2$ occuring in an isothermal and isobaric reactor maintained at $298 K$ and $1.0$ bar. The standard Gibbs energy change of the reaction at $298 K$ is $\Delta G^\circ_{298}=5253 \; J\;mol^{-1}.$ The standard ... initially charged to the reactor, the fraction of $N_2O_4$ that decomposes into $NO_2$ at equilibrium is $0$ $0.17$ $0.38$ $1$
A tank initially contains a gas mixture with $21\:mol\:\%$ oxygen and $79\:mol\:\%$ nitrogen. Pure nitrogen enters the tank, and a gas mixture of nitrogen and oxygen exits the tank. The molar flow rate of both the inlet and exit streams is $8\: mol\: s^{-1}$. In addition, ... time (in seconds) required for oxygen content in the tank to decrease to $1\:mol\:\%$ is $100.45$ $304.45$ $3.445$ $10$
Consider steady, laminar, fully developed flow of an incompressible Newtonian fluid through two horizontal straight pipes, $I$ and $II$, of circular cross section. The volumetric flow rates in both the pipes are the same. The diameter of pipe $II$ is twice the diameter of pipe $I$ ... stress at the wall of pipe $I$ to the shear stress at the wall of pipe $II$ is $0.5$ $2$ $4$ $8$
Equilibrium data for a binary mixture of $E$ and $F$ at two different pressure is shown in the figure. It is desired to process a feed containing $80 \text{ mol } \% E$ and $20 \text{ mol } \% F$ ... high purity $E$ is recovered from the top of column $2$ $P_1=20, P_2=100$, and high purity $E$ is recovered from the bottom of column $2$
A hollow cylinder of equal length and inner diameter (i.e., $L=D$) is sealed at both ends with flat plate, as shown in the figure. Its inner surfaces, $A_1$, $A_2$, and $A_3$ radiate energy. $F_{ij}$ denotes the fraction of radiation energy leaving the surface $A_i$ which reaches the surface $A_j$. It ... $F_{21} = \dfrac{\sqrt{2}-1}{4}$ $F_{21} = \dfrac{\sqrt{2}-1}{8}$
A student performs a flow experiment with Bingham Plastic under fully developed laminar flow conditions in a tube of radius $0.01 \: m$ with a pressure drop $(\Delta P)$ of $10 \: kPa$ over tube length $(L)$ of $1.0 \: m$. The velocity profile is flat for $r<r_c$ and parabolic for ... $r_c$ is $0.001 \: m$, then the magnitude of yield stress for this Bingham Plastic (in $Pa$) is $1$ $5$ $8$ $12$
A feed stream containing pure species $L$ flows into a reactor, where $L$ is partly converted to $M$ as shown in the figure. The mass flow rate of the recycle stream is $20\%$ of that of the product stream. The overall conversion of $L$ (based on mass units) in the process is $30 \%$ ... one-pass conversion of $L$ (based on mass units) through the reactor is $34.2 \%$ $30\%$ $26.3 \%$ $23.8 \%$
A U-tube manometer contains two manometric fluids of densities $1000 \: kg \: m^{-3}$ and $600 \: kg \: m^{-3}$. When both the limbs are open to atmosphere, the difference between the two levels is $10 \: cm$ at equilibrium, as shown in the figure. The rest of the manometer is filled ... limb $'P'$ to raise the fluid in the limb $'Q'$ by another $20 \: cm$? $100.175$ $103.924$ $547.231$ $833.206$
A pure gas obeys the equation of state given by $\dfrac{PV}{RT} = 1 + \dfrac{BP}{RT}$ where $P$ is the pressure, $T$ is the absolute temperature, $V$ is the molar volume of the gas, $R$ is the universal gas constant, and $B$ is a parameter independent of $T$ and $P$. The residual ... molar enthalpy (in $J \: mol^{-1})$ of the gas at $1000 \: kPa$ and $300 \: K$ is $100$ $300$ $2494$ $30000$
Consider one mole of an ideal gas in a closed system. It undergoes a change in state from $L$ to $N$ through two different non-isothermal processes, as shown in the $P-V$ diagram (where $P$ is the pressure and $V$ is the molar volume of the gas). Process $I$ is carried out in a single step ... and that for process $II$ is $Q_{II}$. The value of $Q_I - Q_{II}$ (in $J$) is $250$ $500$ $1000$ $1500$
A fluid is heated from $40^{\circ}C$ to $60^{\circ} C$ in a countercurrent, double pipe heat exchanger. Hot fluid enters at $100^{\circ}C$ and exits at $70^{\circ}C$. The log mean temperature difference, i.e. LMTD (in $^{\circ}C$), is _____ (round off to $2$ decimal places).
Consider an infinitely long rectangular fin exposed to a surrounding fluid at a constant temperature $T_a=27^{\circ}C$. The steady state one dimensional energy balance on an element of the fin of thickness $dx$ at a distance $x$ ... $^{\circ}C$) at $x=25 \: cm$ is __________ (round off to $1$ decimal place).
Liquid water is pumped at a volumetric flow rate of $0.02 \: m^3 s^{-1}$ from Tank $I$ to Tank $II$, as shown in the figure. Both the tanks are open to the atmosphere. The total frictional head loss for the pipe system is $1.0 \: m$ of water. ... surfaces in the tanks have negligible velocities The power supplied (in $W$) by the pump to lift the water is ________ (round off to $1$ decimal place)
An elementary liquid phase reversible reaction $P \leftrightarrows Q$ is carried out in an ideal continuous stirred tank reactor (CSTR) operated at steady state. The rate of consumption of $P, -r_p$ (in $mol \: \text{litre}^{-1} \text{minute}^{-1}$), is ... reaction mixture is constant throughout the operation. The space time (in minutes) of the CSTR is ______ (round off to $1$ decimal place).
An aqueous suspension at $60^{\circ}C$ is fed to the first effect of a double effect forward feed evaporator with a mass flow rate of $1.25 \: kg \: s^{-1}$ ... $kg$ per $kg$) is ____________ (round off to $2$ decimal places).
A vertically held packed bed has a height of $1 \: m$, and void fraction of $0.1$, when there is no flow through the bed. The incipient (minimum) fluidization is set in by injection of a fluid of density $1 \: kg \: m^{-3}$. The particle density $(\rho_p)$ of the solids ... $9.81 \: m \: s^{-2}$. The pressure drop (in $Pa$) across the height of the bed is ________ (round off to nearest integer).
Two ideal cross-current stages operate to extract $P$ from a feed containing $P$ and $Q$, as shown below. The mass flow rates of $P$ and $Q$ fed to Stage $1$ are $1,000 \: kg h^{-1}$ and $10,000 \: kg \: h^{-1}$, respectively. Pure solvent $(S)$ is ... with the raffinate. The mass flow rate of $P$ (in $kg \: h^{-1}$) in the raffinate from Stage $2$ is ________ (round off to nearest integer)
Consider a vertically falling film of water over an impermeable wall. The film is in contact with a static pool of an non-reactive pure gas. The gas diffuses into the water film over the entire height of the falling film. The height of the film is $1.0 \: m$, and its ... (in $mm \: s^{-1}$), averaged over the entire height of the falling film is __________ (round off to $3$ decimal places)
An exothermic, aqueous phase, irreversible, first order reaction, $Y \rightarrow Z$ is carried out in an ideal continuous stirred tank reactor (CSTR) operated adiabatically at steady state. Rate of consumption of $Y$ (in $\text{ mol litre}^{-1} \text{ minute}^{-1}$ ... of the reactor is $90 \%$, the volume of the CSTR (in $\text{litre}$) is ______ (round off to $2$ decimal places)
The liquid phase irreversible reactions, $P \xrightarrow[]{k_1} Q$ and $P \xrightarrow[]{k_2} R$, are carried out in an ideal continuous stirred tank reactor (CSTR) operating isothermally at steady state. The space time of the CSTR is $1$ minute. Both the reactions are first ... $k_1$ (in minute$^{-1}$) is ______ (correct up to one decimal place)