If $$R$$, $$X_L$$ and $$X_C$$ represent resistance, inductive reactance and capacitive reactance. Then which of the following is dimensionless:
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If $$R$$, $$X_L$$ and $$X_C$$ represent resistance, inductive reactance and capacitive reactance. Then which of the following is dimensionless:
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The initial speed of a projectile fired from ground is $$u$$. At the highest point during its motion, the speed of projectile is $$\dfrac{\sqrt{3}}{2}u$$. The time of flight of the projectile is:
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As shown in figure, a 70 kg garden roller is pushed with a force of $$\vec{F} = 200$$ N at an angle of 30° with horizontal. The normal reaction on the roller is (Given $$g = 10$$ m s$$^{-2}$$)

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100 balls each of mass $$m$$ moving with speed $$v$$ simultaneously strike a wall normally and reflected back with same speed, in time $$t$$ s. The total force exerted by the balls on the wall is
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At a certain depth $$d$$ below surface of earth, value of acceleration due to gravity becomes four times that of its value at a height $$3R$$ above earth surface. Where $$R$$ is Radius of earth (Take $$R = 6400$$ km). The depth $$d$$ is equal to
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Spherical insulating ball and a spherical metallic ball of same size and mass are dropped from the same height. Choose the correct statement out of the following {Assume negligible air friction}
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If 1000 droplets of water of surface tension 0.07 N m$$^{-1}$$, having same radius 1 mm each, combine to form a single drop. In the process the released surface energy is- (Take $$\pi = \dfrac{22}{7}$$)
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The pressure of a gas changes linearly with volume from $$A$$ to $$B$$ as shown in figure. If no heat is supplied to or extracted from the gas then change in the internal energy of the gas will be

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The correct relation between $$\gamma = \dfrac{C_P}{C_V}$$ and temperature $$T$$ is:
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The maximum potential energy of a block executing simple harmonic motion is 25 J. A is amplitude of oscillation. At $$\dfrac{A}{2}$$, the kinetic energy of the block is
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Which of the following correctly represents the variation of electric potential $$(V)$$ of a charged spherical conductor of radius $$(R)$$ with radial distance $$(r)$$ from the centre?
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The drift velocity of electrons for a conductor connected in an electrical circuit is $$V_d$$. The conductor is now replaced by another conductor with same material and same length but double the area of cross-section. The applied voltage remains same. The new drift velocity of electrons will be
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A bar magnet with a magnetic moment 5.0 A m$$^2$$ is placed in parallel position relative to a magnetic field of 0.4 T. The amount of required work done in turning the magnet from parallel to antiparallel position relative to the field direction is ________.
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A rod with circular cross-section area 2 cm$$^2$$ and length 40 cm is wound uniformly with 400 turns of an insulated wire. If a current of 0.4 A flows in the wire windings, the total magnetic flux produced inside the windings is $$4\pi \times 10^{-6}$$ Wb. The relative permeability of the rod is
(Given: Permeability of vacuum $$\mu_0 = 4\pi \times 10^{-7}$$ N A$$^{-2}$$)
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Two polaroids $$A$$ and $$B$$ are placed in such a way that the pass-axis of polaroids are perpendicular to each other. Now, another polaroid $$C$$ is placed between $$A$$ and $$B$$ bisecting angle between them. If intensity of unpolarised light is $$I_0$$ then intensity of transmitted light after passing through polaroid $$B$$ will be:
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Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R
Assertion A: The beam of electrons shows wave nature and exhibit interference and diffraction.
Reason R: Davisson Germer Experimentally verified the wave nature of electrons.
In the light of the above statements. Choose the most appropriate answer from the options given below:
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If a source of electromagnetic radiation having power 15 kW produces $$10^{16}$$ photons per second, the radiation belongs to a part of spectrum is:
(Take Planck constant $$h = 6 \times 10^{-34}$$ J s)
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A free neutron decays into a proton but a free proton does not decay into neutron. This is because
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The effect of increase in temperature on the number of electrons in conduction band $$(n_e)$$ and resistance of a semiconductor will be as:
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The amplitude of 15sin(1000$$\pi t$$) is modulated by 10sin(4$$\pi t$$) signal. The amplitude modulated signal contains frequency(ies) of
(A) 500 Hz
(B) 2 Hz
(C) 250 Hz
(D) 498 Hz
(E) 502 Hz
Choose the correct answer from the options given below:
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The speed of a swimmer is 4 km h$$^{-1}$$ in still water. If the swimmer makes his strokes normal to the flow of river of width 1 km, he reaches a point 750 m down the stream on the opposite bank. The speed of the river water is ______ km h$$^{-1}$$.
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A lift of mass $$M = 500$$ kg is descending with speed of 2 m s$$^{-1}$$. Its supporting cable begins to slip thus allowing it to fall with a constant acceleration of 2 m s$$^{-2}$$. The kinetic energy of the lift at the end of fall through to a distance of 6 m will be ______ kJ.
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A solid sphere of mass 1 kg rolls without slipping on a plane surface. Its kinetic energy is $$7 \times 10^{-3}$$ J. The speed of the centre of mass of the sphere is ______ cm s$$^{-1}$$.
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A thin rod having a length of 1 m and area of cross-section $$3 \times 10^{-6}$$ m$$^2$$ is suspended vertically from one end. The rod is cooled from 210°C to 160°C. After cooling, a mass $$M$$ is attached at the lower end of the rod such that the length of rod again becomes 1 m. Young's modulus and coefficient of linear expansion of the rod are $$2 \times 10^{11}$$ N m$$^{-2}$$ and $$2 \times 10^{-5}$$ K$$^{-1}$$, respectively. The value of $$M$$ is ______ kg. (Take $$g = 10$$ m s$$^{-2}$$)
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In the figure given below, a block of mass $$M = 490$$ g placed on a frictionless table is connected with two springs having same spring constant ($$K = 2$$ N m$$^{-1}$$). If the block is horizontally displaced through $$X$$ m then the number of complete oscillations it will make in $$14\pi$$ seconds will be ______.

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Expression for an electric field is given by $$\vec{E} = 4000 \; x^2 \; \hat{i}$$ V m$$^{-1}$$. The electric flux through the cube of side 20 cm when placed in electric field (as shown in the figure) is ______ V cm.

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Two identical cells, when connected either in parallel or in series gives same current in an external resistance 5 $$\Omega$$. The internal resistance of each cell will be ______ $$\Omega$$.
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An inductor of 0.5 mH, a capacitor of 20 $$\mu$$F and resistance of 20 $$\Omega$$ are connected in series with a 220 V ac source. If the current is in phase with the emf, the amplitude of current of the circuit is $$\sqrt{x}$$ A. The value of $$x$$ is-
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In a medium the speed of light wave decreases to 0.2 times to its speed in free space. The ratio of relative permittivity to the refractive index of the medium is $$x$$:1. The value of $$x$$ is ______.
(Given speed of light in free space $$= 3 \times 10^8$$ m s$$^{-1}$$ and for the given medium $$\mu_r = 1$$)
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For hydrogen atom, $$\lambda_1$$ and $$\lambda_2$$ are the wavelengths corresponding to the transitions 1 and 2 respectively as shown in figure. The ratio of $$\lambda_1$$ and $$\lambda_2$$ is $$\dfrac{x}{32}$$. The value of $$x$$ is ______.

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Which transition in the hydrogen spectrum would have the same wavelength as the Balmer type transition from n = 4 to n = 2 of He$$^+$$ spectrum
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The correct increasing order of the ionic radii is
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Match List I with List II
List I List II
A. XeF$$_4$$ I. See-saw
B. SF$$_4$$ II. Square planar
C. NH$$_4^+$$ III. Bent T-shaped
D. BrF$$_3$$ IV. Tetrahedral
Choose the correct answer from the options given below:
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$$H_2O_2$$ acts as a reducing agent in
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Match items of column I and II

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Choose the correct set of reagents for the following conversion
trans Ph - CH = CH - CH$$_3$$ $$\rightarrow$$ cis Ph - CH = CH - CH$$_3$$
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Which one of the following statements is correct for electrolysis of brine solution?
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Adding surfactants in non polar solvent, the micelles structure will look like
(a)
(b)
(c)
(d)

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The methods NOT involved in concentration of ore are
(A) Liquation
(B) Leaching
(C) Electrolysis
(D) Hydraulic washing
(E) Froth floatation
Choose the correct answer from the options given below:
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Identify X, Y and Z in the following reaction. (Equation not balanced)
$$ClO^. + NO_2 \rightarrow X \xrightarrow{H_2O} Y + Z$$
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When Cu$$^{2+}$$ ion is treated with KI, a white precipitate, X appears in solution. The solution is titrated with sodium thiosulphate, the compound Y is formed. X and Y respectively are
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The correct order of basicity of oxides of vanadium is
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Nd$$^{2+}$$ = ______
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Cobalt chloride when dissolved in water forms pink colored complex X which has octahedral geometry. This solution on treating with conc HCl forms deep blue complex, Y which has a Z geometry. X, Y and Z, respectively, are
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The correct order of melting point of dichlorobenzenes is
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An organic compound 'A' with empirical formula C$$_6$$H$$_6$$O gives sooty flame on burning. Its reaction with bromine solution in low polarity solvent results in high yield of B. B is
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Propanal reacts with methanal according to the following sequence:
$$\mathrm{Propanal+Methanal\xrightarrow{(i)\ dil.\ NaOH}\xrightarrow{(ii)\ \Delta}\xrightarrow{(iii)\ NaCN}\xrightarrow{(iv)\ H_3O^+}B}$$
The molecular formula of product $$B$$ is:
$$C_5H_8O_3$$
Identify the correct statement regarding product $$B$$.
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Which of the following artificial sweeteners has the highest sweetness value in comparison to cane sugar?
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A protein 'X' with molecular weight of 70,000 u, on hydrolysis gives amino acids. One of these amino acid is
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On complete combustion, 0.492 g of an organic compound gave 0.792 g of CO$$_2$$. The % of carbon in the organic compound is (Nearest integer)
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Zinc reacts with hydrochloric acid to give hydrogen and zinc chloride. The volume of hydrogen gas produced at STP from the reaction of 11.5 g of zinc with excess HCl is L (Nearest integer)
(Given: Molar mass of Zn is 65.4 g mol$$^{-1}$$ and Molar volume of H$$_2$$ at STP = 22.7 L)
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The enthalpy change for the conversion of $$\dfrac{1}{2}$$Cl$$_2$$(g) to Cl$$^-$$(aq) is (-) ______ kJmol$$^{-1}$$ (Nearest integer)
Given: $$\Delta_{dis}H^0_{Cl_2(g)} = 240$$ kJmol$$^{-1}$$
$$\Delta_{eg}H^o_{Cl(g)} = -350$$ kJmol$$^{-1}$$
$$\Delta_{hyd}H^o_{Cl^-(g)} = -380$$ kJmol$$^{-1}$$
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For reaction: $$SO_2(g) + \dfrac{1}{2}O_2(g) \rightleftharpoons SO_3(g)$$ $$K_P = 2 \times 10^{12}$$ at 27°C and 1 atm pressure. The $$K_c$$ for the same reaction is ______ $$\times 10^{13}$$. (Nearest integer)
(Given $$R = 0.082$$ L atm K$$^{-1}$$ mol$$^{-1}$$)
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The total pressure of a mixture of non-reacting gases X(0.6 g) and Y(0.45 g) in a vessel is 740 mm of Hg. The partial pressure of the gas X is mm of Hg. (Nearest Integer)
(Given: molar mass X = 20 and Y = 45 g mol$$^{-1}$$)
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At 27°C, a solution containing 2.5 g of solute in 250.0 mL of solution exerts an osmotic pressure of 400 Pa. The molar mass of the solute is g mol$$^{-1}$$ (Nearest integer)
(Given: R = 0.083 L bar$$^{-1}$$ mol$$^{-1}$$)
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The logarithm of equilibrium constant for the reaction $$Pd^{2+} + 4Cl^- \rightleftharpoons PdCl_4^{2-}$$ is (Nearest integer)
Given: $$\dfrac{2.303RT}{F} = 0.06$$ V
$$Pd^{2+}_{(aq)} + 2e^- \rightleftharpoons Pd(s)$$ $$E^o = 0.83$$ V
$$PdCl_4^{2-}(aq) + 2e^- \rightleftharpoons Pd(s) + 4Cl^-(aq)$$ $$
$$E^o = 0.65$$ V
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$$A \rightarrow B$$
The rate constants of the above reaction at 200 K and 300 K are 0.03 min$$^{-1}$$ and 0.05 min$$^{-1}$$ respectively. The activation energy for the reaction is J (Nearest integer)
(Given: ln 10 = 2.3, R = 8.3 J K$$^{-1}$$ mol$$^{-1}$$, log 5 = 0.70, log 3 = 0.48, log 2 = 0.30)
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The oxidation state of phosphorus in hypophosphoric acid is
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How many of the transformation given below would result in aromatic amines?

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The number of real roots of the equation $$\sqrt{x^2 - 4x + 3} + \sqrt{x^2 - 9} = \sqrt{4x^2 - 14x + 6}$$, is:
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For all $$z \in C$$ on the curve $$C_1$$: $$|z| = 4$$, let the locus of the point $$z + \dfrac{1}{z}$$ be the curve $$C_2$$. Then
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If the sum and product of four positive consecutive terms of a G.P., are 126 and 1296, respectively, then the sum of common ratios of all such GPs is
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Let a circle $$C_1$$ be obtained on rolling the circle $$x^2 + y^2 - 4x - 6y + 11 = 0$$ upwards 4 units on the tangent T to it at the point (3, 2). Let $$C_2$$ be the image of $$C_1$$ in T. Let $$A$$ and $$B$$ be the centers of circles $$C_1$$ and $$C_2$$ respectively, and $$M$$ and $$N$$ be respectively the feet of perpendiculars drawn from $$A$$ and $$B$$ on the x-axis. Then the area of the trapezium AMNB is:
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If the maximum distance of normal to the ellipse $$\dfrac{x^2}{4} + \dfrac{y^2}{b^2} = 1, b < 2$$, from the origin is 1, then the eccentricity of the ellipse is:
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Consider:
S1: $$p \Rightarrow q \lor p \land \sim q$$ is a tautology.
S2: $$\sim p \Rightarrow \sim q \land \sim p \lor q$$ is a contradiction.
Then
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Let $$R$$ be a relation on $$N \times N$$ defined by $$a, b R c, d$$ if and only if $$ad(b - c) = bc(a - d)$$. Then $$R$$ is
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Let $$A = \begin{pmatrix} 1 & 0 & 0 \\ 0 & 4 & -1 \\ 0 & 12 & -3 \end{pmatrix}$$. Then the sum of the diagonal elements of the matrix $$(A + I)^{11}$$ is equal to:
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For the system of linear equations
$$x + y + z = 6$$
$$\alpha x + \beta y + 7z = 3$$
$$x + 2y + 3z = 14$$
which of the following is NOT true?
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If $$\sin^{-1}\dfrac{\alpha}{17} + \cos^{-1}\dfrac{4}{5} - \tan^{-1}\dfrac{77}{36} = 0$$, $$0 < \alpha < 13$$, then $$\sin^{-1}\sin\alpha + \cos^{-1}\cos\alpha$$ is equal to
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Let $$y = fx$$ represent a parabola with focus $$(-\dfrac{1}{2}, 0)$$ and directrix $$y = -\dfrac{1}{2}$$. Then
$$S = \{x \in \mathbb{R}: \tan^{-1}(\sqrt{fx}) + \sin^{-1}(\sqrt{fx+1}) = \dfrac{\pi}{2}\}$$:
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If the domain of the function $$f(x) = \dfrac{x}{1 + x^2}$$, where $$x$$ is greatest integer $$\le x$$, is $$[2, 6)$$, then its range is
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Let $$y = f(x) = \sin^3\left(\frac{\pi}{3} \cos\left(\frac{\pi}{3\sqrt{2}}(-4x^3 + 5x^2 + 1)^{\frac{3}{2}}\right)\right)$$. Then, at $$x = 1$$,
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A wire of length 20 m is to be cut into two pieces. A piece of length $$\ell_1$$ is bent to make a square of area $$A_1$$ and the other piece of length $$\ell_2$$ is made into a circle of area $$A_2$$. If $$2A_1 + 3A_2$$ is minimum then $$\pi\ell_1 : \ell_2$$ is equal to:
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Let $$\alpha \in (0, 1)$$ and $$\beta = \log_e(1 - \alpha)$$. Let $$P_n(x) = x + \dfrac{x^2}{2} + \dfrac{x^3}{3} + \ldots + \dfrac{x^n}{n}$$, $$x \in (0, 1)$$. Then the integral $$\int_0^{\alpha} \dfrac{t^{50}}{1-t} dt$$ is equal to
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The value of $$\int_{\frac{\pi}{3}}^{\frac{\pi}{2}} \dfrac{2 + 3\sin x}{\sin x(1 + \cos x)} dx$$ is equal to
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Let a differentiable function $$f$$ satisfy $$f(x) + \int_3^x \dfrac{f(t)}{t} dt = \sqrt{x+1}$$, $$x \ge 3$$. Then $$12f(8)$$ is equal to:
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Let $$\vec{a} = 2\hat{i} + \hat{j} + \hat{k}$$, and $$\vec{b}$$ and $$\vec{c}$$ be two nonzero vectors such that $$\vec{a} + \vec{b} + \vec{c} = \vec{a} + \vec{b} - \vec{c}$$ and $$\vec{b} \cdot \vec{c} = 0$$. Consider the following two statements:
A: $$\vec{a} + \lambda\vec{c} \ge \vec{a}$$ for all $$\lambda \in \mathbb{R}$$.
B: $$\vec{a}$$ and $$\vec{c}$$ are always parallel.
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Let the shortest distance between the lines L: $$\dfrac{x-5}{-2} = \dfrac{y-\lambda}{0} = \dfrac{z+\lambda}{1}$$, $$\lambda \ge 0$$ and L$$_1$$: $$x+1 = y-1 = 4-z$$ be $$2\sqrt{6}$$. If $$(\alpha, \beta, \gamma)$$ lies on L, then which of the following is NOT possible?
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A bag contains 6 balls. Two balls are drawn from it at random and both are found to be black. The probability that the bag contains at least 5 black balls is
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Let 5 digit numbers be constructed using the digits 0, 2, 3, 4, 7, 9 with repetition allowed, and are arranged in ascending order with serial numbers. Then the serial number of the number 42923 is ______.
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Let $$a_1, a_2, \ldots, a_n$$ be in A.P. If $$a_5 = 2a_7$$ and $$a_{11} = 18$$, then $$12\left(\dfrac{1}{\sqrt{a_{10}} + \sqrt{a_{11}}} + \dfrac{1}{\sqrt{a_{11}} + \sqrt{a_{12}}} + \ldots + \dfrac{1}{\sqrt{a_{17}} + \sqrt{a_{18}}}\right)$$ is equal to ______.
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Number of 4-digit numbers that are less than or equal to 2800 and either divisible by 3 or by 11, is equal to ______.
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Let $$\alpha > 0$$, be the smallest number such that the expansion of $$\left(x^{\frac{2}{3}}+\frac{2}{x^3}\right)^{30}$$ has a term $$\beta x^{-\alpha}$$, $$\beta \in N$$. Then $$\alpha$$ is equal to ______.
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The remainder on dividing $$5^{99}$$ by 11 is ______.
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If the variance of the frequency distribution
is 3, then $$\alpha$$ is equal to ______.
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Let for $$x \in R$$, $$f(x) = \dfrac{x+x}{2}$$ and $$g(x) = \begin{cases} x, & x < 0 \\ x^2, & x \ge 0 \end{cases}$$. Then area bounded by the curve $$y = f \circ g(x)$$ and the lines $$y = 0, 2y - x = 15$$ is equal to ______.
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Let $$\vec{a}$$ and $$\vec{b}$$ be two vectors such that $$\vec{a} = \sqrt{14}$$, $$\vec{b} = \sqrt{6}$$ and $$|\vec{a} \times \vec{b}| = \sqrt{48}$$. Then $$(\vec{a} \cdot \vec{b})^2$$ is equal to ______.
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Let the line $$L$$: $$\dfrac{x-1}{2} = \dfrac{y+1}{-1} = \dfrac{z-3}{1}$$ intersect the plane $$2x + y + 3z = 16$$ at the point $$P$$. Let the point $$Q$$ be the foot of perpendicular from the point $$R(1, -1, -3)$$ on the line $$L$$. If $$\alpha$$ is the area of triangle $$PQR$$, then $$\alpha^2$$ is equal to ______.
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Let $$\theta$$ be the angle between the planes $$P_1 = \vec{r} \cdot (\hat{i} + \hat{j} + 2\hat{k}) = 9$$ and $$P_2 = \vec{r} \cdot (2\hat{i} - \hat{j} + \hat{k}) = 15$$. Let L be the line that meets $$P_2$$ at the point (4, -2, 5) and makes angle $$\theta$$ with the normal of $$P_2$$. If $$\alpha$$ is the angle between L and $$P_2$$ then $$\tan^2\theta \cot^2\alpha$$ is equal to ______.
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