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Recent questions tagged gate2018

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A hot liquid is to be cooled in a $1-1$ shell and tube heat exchanger from $80^{\circ}C$ to $50^{\circ}C$. Cooling water enters the tube side at $30^{\circ}C$, and exits at $45^{\circ}C$. The properties of the liquids are constant ... percentage saving in heat transfer area for counter-current option with respect to the area of co-current option is __________ (rounded off to third decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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In a roll crusher, rolls of diameter $1$ $m$ each are set in such a manner that minimum clearance between the crushing surfaces is $15$ $mm$. If the angle of nip is $31^{\circ}$, the maximum diameter of the particle (in $mm$) which can be crushed is ___________ (rounded off to third decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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The humidity of air at a dry-bulb temperature of $65^{\circ}\:C$ is $0.025$ $kg$ water/$kg$ dry air. The latent heat of vaporization of water at $0^{\circ}\:C$ is $2500$ $kJ/kg$. The psychrometric ratio of air is $0.95$ $kJ$ ($kg$ dry ... , the enthalpy of air (in $kJ/kg$) at its adiabatic saturation temperature of $35^{\circ}\:C$ is ____________________ (rounded off to two decimal places).
asked Feb 20, 2018 in Others gatecse 1.4k points
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Hydrogenation of benzene is to be carried out using $Ni$ (density = $8910$ $kg/m^{3}$) as catalyst, cast in the from of non-porous hollow cylinders, as shown below. The reaction occurs on all the surfaces of the hollow cylinder. During an experiment, one such cylinder ... rate of reaction in mol($kg$ of catalyst)$^{-1}$ min$^{-1}$ is ________________________ (rounded off to three decimal places).
asked Feb 20, 2018 in Others gatecse 1.4k points
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For a closed-loop system, consider the following transfer functions: process $G_{p}\left ( s \right )$, controller $G_{c}\left ( s \right )$, measuring device $G_{m}\left ( s \right )$, and final control element $G_{f}\left ( s \right )$ ... The offset in the closed loop response due to a unit step change introduced in the set point of the output variable is ___________.
asked Feb 20, 2018 in Others gatecse 1.4k points
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A set of standard stainless steel pipes, each of internal diameter $26.65\:mm$ and $6000\:mm$ length, is used to make a plug flow reactor by joining them in series to carry out degradation of polyethylene. Seven such pipes are required to obtain a ... pipes of the same internal diameter to be procured for obtaining at least $66\%$ conversion under the same reaction condition is _______________.
asked Feb 20, 2018 in Others gatecse 1.4k points
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In a closed piston-cylinder system, methane was observed to obey the following equation of state $P\left ( V-nb \right )=nRT$ where $b=0.029\:m^{3}$/mol. The temperature and volume are $500 \:^{\circ}C$ and $5\:m^{3}$ respectively for $100$ moles of ... system, the isobaric rate of change of temperature with volume (in $^{\circ}C\:/m^{3}$) is ________________ (rounded off to second decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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For the matrix $A=\begin{bmatrix} cos\theta &-sin\theta \\ sin \theta & cos\theta \end{bmatrix}$ if $det$ stands for the determinant and $A^{T}$ is the transpose of $A$ then the value of $det(A^{T}\:A)$ is _____________
asked Feb 20, 2018 in Others gatecse 1.4k points
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An azeotropic mixture of ethanol and water is to be separated in a distillation column using benzene as an entrainer. At the column operating conditions, two liquid phases are formed on a tray. The degree($s$) of freedom of the system for the choice intensive properties at equilibrium is (are) ________________
asked Feb 20, 2018 in Others gatecse 1.4k points
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The volume of liquid filled in a spherical storage tank of radius $R$ is computed from height of liquid, $h$, in the outside tube (neglecting the volume of liquid in the outside tube) as $V=\pi h^{2}\frac{\left ( 3R-h \right )}{3}$. The estimate of ... of Secant method, using $1\:m$ and $3\:m$ as tow initial guesses of liquid height is _________________ (rounded off to second decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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If $y=e^{-x^{2}}$ then the value of $\underset{x\rightarrow \infty }{lim}\frac{1}{x}\frac{dy}{dx}$ is __________
asked Feb 20, 2018 in Others gatecse 1.4k points
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Consider the following transfer function: $G\left ( s \right )=\frac{3}{\left ( 5s+1 \right )^{2}}$ where, the natural period of oscillation is in min. The amplitude ratio at a frequency of $0.5$ rad/min is ________________ (rounded off to second decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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A fiberboard sheet $\left ( 1.5\:m\times 2.0\:m\times 15\:mm \right )$ is being dried by suspending it horizontally in a current of hot, dry air. The edges are insulted so that drying takes place only from the top and bottom surfaces. The wet ... contents are on dry basis. The time required for drying during constant rate period (in hour) is ________________ (rounded off to third decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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Under isothermal condition, a vertical tube of length $L=100\:m$ contains a gas of molecular weight equal to $60$. The pressure and temperature at the top of the tube are $100\:kPa$ and $25\:^{\circ}C$respectively. Consider the universal gas constant and acceleration ... the gas is ideal, the pressure (in $kPa$) at the bottom of the tube will be ______________ (rounded off to third decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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A binary distillation column is designed by McCabe-Thiele method to get a distillate mole fraction of $0.9$. The enriching section operating line has an intercept with $y$-axis at $0.3$ mole fraction. The ratio of liquid to vapour molar flow rate in the enriching section is ___________ (rounded off to third decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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An insulted storage tank contains $1000\:kg$ liquid of specific heat $10\:kJ\:kg^{-1}\:K^{-1}$. The liquid is heated by saturated steam, condensing in a helical coil at a temperature of $180 \:^{\circ}C$. The heat transfer area of the coil is $0.1\:m^{2}$. ... temperature of the liquid in the tank from $20 \:^{\circ}C$ to $80 \:^{\circ}C$ is ________________ (rounded off to second decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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Vapour bubbles are formed in the nucleate boiling regime at a frequency of $10$ bubbles per second per nucleation site. There are $100$ nucleation sites per $m^{2}$ of heating area. The latent heat of vapourization and the density of vapour under the operating condition are ... generation. The heat flux (in Watt per $m^{2}$ of heating area) is _______________ (rounded off to third decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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A $CSTR$ and a $PFR$ of equal volume are connected in series as shown below to carry out a first-order, isothermal, liquid phase reaction $A{\rightarrow}P$ The rate constant is $0.2\:s^{-1}$. The space-time is $5\:s$ for both the reactors. The overall fractional conversion of $A$ is _____________ (rounded off to third decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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It is decided to extract $A$ from a feed containing $20$ mol$\%$ $A$ and $80$ mol$\%$ $B$ in two ideal cross-current stages as shown below, using equal amount of pure solvent $C$ in each stage. Components $B$ and $C$ are immiscible. $60\%$ of ... in extract in equilibrium with raffinate The mol $\%$ of $A$ in raffinate from $Stage\:2$ is ___________________ (rounded off to second decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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At a shear rate of $10\:s^{-1}$, the apparent viscosity of a non-Newtonian liquid was found to be $1\: Pa\:s$. At a shear rate of $100\:s^{-1}$, the apparent viscosity of the same liquid was found to be $0.5\:Pa\:s$. If the liquid follows power law behavior, the apparent viscosity (in $Pa\:s$) at a shear stress of $10\:N\:m^{-2}$ is ______________ (rounded off two decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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The wall of a pipe of radius $1\:m$ is at a uniform temperature of $200\:^{\circ}C$, and is covered by insulation of thickness $0.1\:m$. The ambient air outside the insulated pipe is at $20\:^{\circ}C$ ... occurs at steady state, the temperature (in $^{\circ}C$) of the outer surface of insulation is ____________________ (rounded off to second decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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The elementary second-order liquid phase reaction $A+B{\rightarrow}C+D$ is carried out in an isothermal plug flow reactor of $2\:m^{3}$ volume. The inlet volumetric flow rate is $10\:m^{3}/h$. The initial concentration of both $A$ and $B$ are $2\: k$mol/$m^{3}$. The rate constant is given as $2.5\:m^{3}\:k$mol$^{-1}$ $h^{-1}$. The percentage conversion of $A$ is ______________.
asked Feb 20, 2018 in Others gatecse 1.4k points
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A furnace installed at a cost of $Rs.\:24$ Lakh is expected to serve its useful life of $5$ years. Salvage value of the furnace is $Rs.\:8$ Lakh. The interest rate compounded annually is $8\%$. The estimated capitalized cost (in Lakhs of rupees ) is $30$ $34.09$ $34.9$ $58.09$
asked Feb 20, 2018 in Others gatecse 1.4k points
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$G$ denotes the Gibbs free energy of a binary mixture, $n_{T}$ denotes the total number of moles present in the system, $\mu _{i}$ is the chemical potential of the $i^{th}$ component $\left ( \mu _{i} \neq 0\:and \:\mu _{1}> \mu _{2}\right )$ and $x_{i}$ is the mole fraction of the $i^{th}$ component. The correct variation of $G/n_{T}$ (in $J$/mol) at constant temperature and pressure is given by
asked Feb 20, 2018 in Others gatecse 1.4k points
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The decay ratio for a system having complex conjugate poles as $\left ( -\frac{1}{10}+j\frac{2}{15} \right )$ and $\left ( -\frac{1}{10}-j\frac{2}{15} \right )$ is $7\times 10^{-1}$ $8\times 10^{-2}$ $9\times 10^{-3}$ $10\times 10^{-4}$
asked Feb 20, 2018 in Others gatecse 1.4k points
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Match the items in Column $A$ with the items in Column $B$ $\begin{array}{|cl|cI|}\hline &\text{$Column\:A$} & \text{$Column\:A$} \\ \hline &\text{P. Pure dead-time} & \text{I. $\phi =-90^{\circ}$} \\ &\text{Q. Pure capacitive} & \text{II. $\frac{K_{1}}{s}-\frac{K_{2}}{\tau s+1}$ with $K_{2}> ... $P-III,\:Q-II,\:R-IV\:S-I$ $P-I,\:Q-IV,\:R-II,\:S-III$ $P-IV,\:Q-I,\:R-II,\:S-III$
asked Feb 20, 2018 in Others gatecse 1.4k points
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A person is drowning in sea at location $R$ and the lifeguard is standing at location $P$. The beach boundary is straight and horizontal, as shown in the figure. The lifeguard runs at a speed of $V_{L}$ and swims at a speed of $V_{s}$. In order to reach to the drowning person in optimum time , the ... $\frac{sin\Theta _{L}}{sin\Theta _{S}}=\frac{V_{L}}{V_{S}}$
asked Feb 20, 2018 in Others gatecse 1.4k points
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In a laboratory batch setup, reaction of $P$ over a catalyst was studied at various temperature. The reactions occurring are $P\rightarrow 2Q\:;\:P\rightarrow R$ At the end of one hour of operation, the batch contains $x_{P},\:x_{Q}$ and $x_{R}$ mole fraction of $P,Q$ and ... found to be $0.40$, then the value of $Y_{Q}$ at $60\:^{\circ}C$ is ________________ (rounded off to second decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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In the year $2005$, the cost of a shell and tube heat exchanger with $68\:m^{2}$ heat transfer area was $Rs.\:12.6$ Lakh. Chemical Engineering Index for cost in $2005$ was $509.4$ and now the index is $575.4$. Based on index of $0.6$ for capacity scaling, the present ... rupees) of a similar heat exchanger having $100\:m^{2}$ heat transfer area is estimated to be $17.94$ $19.94$ $20.94$ $22.94$
asked Feb 20, 2018 in Others gatecse 1.4k points
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For a chemical reaction, the ratio of rate constant at $500\:K$ to that at $400\:K$ is $2.5$. Given $R=8.314\:J$ mol$^{-1}$ $K^{-1}$, the value of activation energy (in $kJ$/mol) is $10.5$ $12.0$ $15.2$ $18.4$
asked Feb 20, 2018 in Others gatecse 1.4k points
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Pitot tube is used to measure liquid level in a tank flow velocity at a point angular deformation vorticity
asked Feb 20, 2018 in Others gatecse 1.4k points
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A first-order process having a transfer function, $G_{p}=\frac{2}{7s+1}$ is controlled by a proportional controller with gain of $3.2$. The process time constant is in minutes. Addition of the integral control action with an integral time constant of $5$ minutes leads to increase in offset speed of response order of the closed loop system proportional band
asked Feb 20, 2018 in Others gatecse 1.4k points
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According to the surface renewal theory, the unit of fractional rate of surface renewal is m$^{2}$ s$^{-2}$ m$^{2}$ s$^{-1}$ m s$^{-1}$ $s^{-1}$
asked Feb 20, 2018 in Others gatecse 1.4k points
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Match the equipment in Column $A$ with the corresponding process in Column $B$ $\begin{array}{|cl|cI|cI|cI|cI|cI|}\hline &\text{$Column\:A$} & \text{$ ... $P-IV, \: Q-I,\:R-II,\:S-III$ $P-IV, \: Q-III,\:R-I,\:S-II$
asked Feb 20, 2018 in Others gatecse 1.4k points
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A venturi meter is installed to measure the flow rate of water in a $178\:mm$ diameter ($ID$) pipe. The throat diameter is $102\:mm$. The differential pressure measured using a manometer is $154.3\:kN/m^{2}$. The data given are: discharge coefficient=$0.98$; water density=$1000\:kg/m^{3}$. The volumetric flow rate of water (in m$^{3}/s$) is _____________.
asked Feb 20, 2018 in Others gatecse 1.4k points
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The ammonia ($NH_{3}$) oxidation process occurs over a catalyst as $4NH_{3}+5O_{2}\rightarrow 6H_{2}O+4NO$ Air is supplied such that oxygen ($O_{2}$) is $20\%$ in excess of that required for complete conversion of $NH_{3}$. The mole fraction of $O_{2}$ in inlet gas mixture ($NH_{3}$+ air ) is _______________ (rounded off to third decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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The inital water level in a tank is $4\:m$. When the value located at the bottom is opened, the rate of change of water level ($L$) with respect to time ($t$) is, $\frac{dL}{dt}=-k\sqrt{t}$, where $k=0.6\:m\:s^{-3/2}$. The level of water (in $m$) in the tank at time $0.5\:s$ after opening the valve is _______________ (rounded off to second decimal place).
asked Feb 20, 2018 in Others gatecse 1.4k points
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For absorption of $H_{2}S$ from a mixture with hydrocarbon vapour into an aqueous alkanolamine solution, the liquid phase mass transfer resistance is significantly higher than that of the gas phase negligible compared to that of the gas phase equal to that of the gas phase dependent on the gas phase mass transfer resistance
asked Feb 20, 2018 in Others gatecse 1.4k points
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In connection with petroleum refining, identify the incorrect statement among the following options. Desalting of crude oil is done before processing it in atmospheric distillation unit A stream of hydrogen is produced in catalytic reforming of naphtha Asphalt used for paving is a petroleum product Cetane number indicates the quality of petrol/motor spirit
asked Feb 20, 2018 in Others gatecse 1.4k points
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Two packed towers are designed for the same mass velocity of the gas. The first has liquid and gas flow rates of $30\:kg/s$ and $1.2\:kg/s$, respectively, while the corresponding flow rates in the second tower are $67.5\:kg/s$ and $1.8\:kg/s$. The ratio of the design diameter of the wider tower to that of the narrower tower is $2$ $1.8$ $1.5$ $1.2225$
asked Feb 20, 2018 in Others gatecse 1.4k points
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