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A piston filled with $0.04\; mol$ of an ideal gas expands reversibly from $50.0 \;mL$ to $375\;mL$ at a constant temperature of $37.0^{\circ} C$. As it does so, it absorbs $208\; J$ of heat. The values of q and w for the process will be

asked Apr 4, 2017 by meena.p

1 answer

Given : $E^0_{Cr^{3+}/Cr} =-0.74\;V ; E^0_{MnO^{-}_4/Mn^{2+}}=1.51\;V $$E^0_{Cr_2O^{2-}_7/Cr^{3+}} =-1.33\;V ; E^0_{Cl/Cl^{-}}=1.36\;V $ Based on the data given above, strongest oxidising agent will be :

asked Apr 4, 2017 by meena.p

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A solution of $(−)−1− chloro − 1− phenylethane$ in toluene racemises slowly in the presence of a small amount of $SbCl_5$ ,due to the formation of :

asked Apr 4, 2017 by meena.p

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Which one of the following molecules is expected to exhibit diamagnetic behaviour ?

asked Apr 4, 2017 by meena.p

1 answer

Which of the following complex species is not expected to exhibit optical isomerism ?

asked Apr 4, 2017 by meena.p

1 answer

A charge Q is uniformly distributed over a long rod AB of length L as shown in the figure. The electric potential at the point O lying at a distance L from the end A is :

asked Apr 3, 2017 by meena.p

1 answer

Two short bar magnets of length 1 cm each have magnetic moments $1.20\; Am^2$ and $1.00 Am^2$ respectively. They are placed on a horizontal table parallel to each other with their N poles pointing towards the South. They have a common magnetic equator and are separated by a distance of $20.0\; cm$. The value of the resultant horizontal magnetic induction at the mid - point O of the line joining their centre is close to (Horizontal component of earth′s magnetic induction is $3.6 \times 10^{−5} Wb / m^2)$

asked Apr 3, 2017 by meena.p

1 answer

Two charges, each equal to q, are kept at $x = − a$ and $x = a$ on the x−axis. A particle of mass $m$ and charge $q_0 = \large\frac{q}{2}$ is placed at the origin. If charge $q_0$ is given a small displacement $(y << a)$along the y−axis, the net force acting on the particle is proportional to :

asked Apr 3, 2017 by meena.p

1 answer

The graph between angle of deviation $(\delta)$ and angle of incidence (i) for a triangular prism is represented by :

asked Apr 3, 2017 by meena.p

1 answer

Assume that a drop of liquid evaporates by decrease in its surface energy. So that its temperature remains unchanged. What should be the minimum radius of the drop for this to be possible? The surface tension is $T$, density of liquid is $\rho$ and $L$ is its latent heat of vaporization.

asked Apr 3, 2017 by meena.p

1 answer

The I − V characteristic of an LED is :

asked Apr 3, 2017 by meena.p

1 answer

The anode voltage of a photocell is kept fixed. The wavelength λ of the light falling on the cathode is gradually changed. The plate current I of the photocell varies as follows :

asked Apr 3, 2017 by meena.p

1 answer

The magnetic field in a travelling electromagnetic wave has a peak value of $20\;nT$. The peak value of electric field strength is :

asked Apr 3, 2017 by meena.p

1 answer

Two coherent point sources $S_1$ and $S_2$ are separated by a small distance 'd' as shown. The fringes obtained on the screen will be :

asked Mar 30, 2017 by meena.p

1 answer

In an LCR circuit as shown below both switches are open initially. Now switch $S_1$ is closed, $S_2$ kept open. (q is charge on the capacitor and $\tau = RC$ is Capacitive time constant). Which of the following statement is correct?

asked Mar 30, 2017 by meena.p

1 answer

This question has statement I and Statement II. Of the four choices given after the Statements, choose the one that best describes the two statements. <br>Statement − I : Higher the range, greater is the resistance of ammeter. <br> Statement − II : To increase the range of ammeter, additional shunt needs to be used across it.

asked Mar 30, 2017 by meena.p

1 answer

If a piece of metal is heated to temperature $\theta$ and then allowed to cool in a room which is at temperature $\theta_0$, the graph between the temperature $T$ of the metal and time $t$ will be closed to :

asked Mar 30, 2017 by meena.p

1 answer

An ideal gas enclosed in a vertical cylindrical container supports a freely moving piston of mass M. The piston and the cylinder have equal cross sectional area A. When the piston is in equilibrium, the volume of the gas is $V_0$ and its pressure is $P_0$. The piston is slightly displaced from the equilibrium position and released. Assuming that the system is completely isolated from its surrounding, the piston executes a simple harmonic motion with frequency :

asked Mar 29, 2017 by meena.p

1 answer

A hoop of radius r and mass m rotating with an angular velocity $\omega$ is placed on a rough horizontal surface. The initial velocity of the centre of the hoop is zero. What will be the velocity of the centre of the hoop when it ceases to slip ?

asked Mar 29, 2017 by meena.p

1 answer

The above p-v diagram represents the thermodynamic cycle of an engine, operating with an ideal monoatomic gas. The amount of heat, extracted from the source in a single cycle is :

asked Mar 29, 2017 by meena.p

1 answer

The supply voltage to a room is $120\; V$. The resistance of the lead wires is $6 \Omega$ . A $60\;W$ bulb is already switched on. What is the decrease of voltage across the bulb, when a $240\; W$ heater is switched on in parallel to the bulb?

asked Mar 29, 2017 by meena.p

1 answer

A beam of unpolarised light of intensity $I_0$ is passed through a polaroid $A$ and then through another polaroid $B$ which is oriented so that its principal plane makes an angle of $45^{\circ}$ relative to that of A. The intensity of the emergent light is :

asked Mar 29, 2017 by meena.p

1 answer

A diode detector is used to detect an amplitude modulated wave of $60\%$ modulation by using a condenser of capacity $250$ pico farad in parallel with a load resistance 100 kilo ohm. Find the maximum modulated frequency which could be detected

asked Mar 28, 2017 by meena.p

1 answer

What is the minimum energy required to launch a satellite of mass $m$ from the surface of a planet of mass $M$ and radius $R$ in a circular orbit at an altitude of $2R$ ?

asked Mar 28, 2017 by meena.p

1 answer

Diameter of a plano - convex lens is $6\;cm$ and thickness at the centre is $3\;mm$. If speed of light in material of lens is $2 × 10^8\; m/s,$ the focal length of the lens is :

asked Mar 28, 2017 by meena.p

1 answer

A circular loop of radius $0.3\; cm$ lies parallel to a much bigger circular loop of radius $20\; cm$. The centre of the small loop is on the axis of the bigger loop. The distance between their centres is $15 cm$. If a current of $2.0\;cm$ A flows through the smaller loop, then the flux linked with bigger loop is:

asked Mar 28, 2017 by meena.p

1 answer

A sonometer wire of length $1.5\;m$ is made of steel. The tension in it produce an elastic strain of $1\%$.What is the fundamental frequency of steel if density and elasticity of steel are $7.7 \times 10^3\; kg / m^3$and $2.2 \times 10^{11}\; N/m^2$ respectively ?

asked Mar 27, 2017 by meena.p

1 answer

Two capacitors $C_1$ and $C_2$ are charged to $120\;V$ and $200\; V$ respectively. It is found that by connecting them together the potential on each one can be made zero. Then :

asked Mar 27, 2017 by meena.p

1 answer

The amplitude of a damped oscillator decreases to $0.9$ times its original magnitude in $5s$. In another $10\;s$ it will decrease to α times its original magnitude, where $\alpha$ equals :

asked Mar 27, 2017 by meena.p

1 answer

A Projectile is given an initial velocity of $(\hat{i}+2 \hat{j})m/s,$ where $\hat i$ is along the ground and $\hat j$ is along the vertical. If $g = 10 m/s^2,$ the equation of its trajectory is :

asked Mar 27, 2017 by meena.p

1 answer

Let $[\in_0]$ denote the dimensional formula of the permittivity of vacuum. If M = mass, L = length, T = Time and A = electric current, then:

asked Mar 27, 2017 by meena.p

1 answer

This question has statement I and Statement II. Of the four choice given after the statements,choose the one that best describes the two statements.<br> Statement – I : A Point particle of mass m moving with speed v collides with stationary pointparticle of mass M. If the maximum energy loss possible is given as $f \bigg(\large\frac{1}{2}$$mv^2\bigg) $ then $f= \bigg(\large\frac{m}{M+m}\bigg)$<br> Statement – II : Maximum energy loss occurs when the particles get stuck together as a result ofthe collision.

asked Mar 22, 2017 by meena.p

1 answer

A metallic rod of length $‘A’$ is tied to a string of length $2A$ and made to rotate with angular speed $\omega$ on a horizontal table with one end of the string fixed. If there is a vertical magnetic field ‘B’ in the region, the e.m.f. induced across the ends of the rod is :

asked Mar 22, 2017 by meena.p

1 answer

A uniform cylinder of length L and mass M having cross - sectional area A is suspended, with its length vertical, from a fixed point by a massless spring, such that it is half submerged in a liquid of density σ at equilibrium position. The extension $x_0$ of the spring when it is in equilibrium is : (Here, k is spring constant)

asked Mar 22, 2017 by meena.p

1 answer

The Boolean Expression $(p \wedge \sim q) \vee q \vee (\sim p \wedge q)$\ is quivalent to :

asked Mar 22, 2017 by meena.p

1 answer

A man is walking towards a vertical pillar in a straight path, at a uniform speed. At a certain point A on the path, he observes that the angle of elevation of the top of the pillar is $30^{\circ}$. After walking for 10 minutes from A in the same direction, at a point B, he observes that the angle of elevation of the top of the pillar is $60^{\circ}$. Then the time taken (in minutes) by him, from B to reach the pillar, is :

asked Mar 22, 2017 by meena.p

1 answer

If $0 \leq x < 2 \pi$, then the number of real values of $x$, which satisfy the equation $\cos x + \cos 2x = \cos 3x + \cos 4x = 0,$ is :

asked Mar 22, 2017 by meena.p

1 answer

Let two fair six-faced dice A and B be thrown simultaneously. If $E_1$ is the event that die $A$ shows up four, $E_2$ is the event that die B shows up two and $E_3$ is the event that the sum of numbers on both dice is odd, then which of the following statements is NOT true?

asked Mar 21, 2017 by meena.p

1 answer

If the standard deviation of the numbers $2, 3, a$ and $11$ is $3.5,$ then which of the following is true?

asked Mar 21, 2017 by meena.p

1 answer

Let $\overrightarrow{a}, \overrightarrow{b}$ and $\overrightarrow{c}$be three unit vectors such that $\overrightarrow{a} \times (\overrightarrow{b} \times \overrightarrow{c}) = \large\frac{3}{2}(\overrightarrow{b}+\overrightarrow{c})$. If $\overrightarrow{b}$ If $\overrightarrow{b}$ is not parallel to $\overrightarrow{c}$ , then the angle between $\overrightarrow{a}$ and $\overrightarrow{b}$ is :

asked Mar 21, 2017 by meena.p

1 answer

If the line, $\large\frac{x-3}{2} =\frac{y+2}{-1}=\frac{z-4}{3}$ lies in the plane,$lx + my - z = 9,$ then $l^2+m^2$ is equal to :

asked Mar 21, 2017 by meena.p

1 answer

The eccentricity of the hyperbola whose length of the latus rectum is equal to 8 and the length of its conjugate axis is equal to half the distance between its foci, is:

asked Mar 21, 2017 by meena.p

1 answer

Let P be the point on the parabola, $y^2= 8x$ which is at a minimum distance from the centre $C$ of the circle, $x^2+(y + 6)^2= 1.$ Then the equation of the circle, passing through C and having its centre at P is:

asked Mar 21, 2017 by meena.p

1 answer

If one of the diameters of the circle, given by the equation, $x^2 + y^2-4x+6y -12 = 0,$ is a chord of a circle S, whose centre is at $(-3, 2),$ then the radius of S is:

asked Mar 21, 2017 by meena.p

1 answer

The centres of those circles which touch the circle, $x^2+y^2- 8x -8y-4 = 0,$ externally and also touch the x-axis, lie on:

asked Mar 21, 2017 by meena.p

1 answer

Two sides of a rhombus are along the lines, $x = y + 1 = 0$ and $7x - y - 5 = 0$. If its diagonals intersect at $(-1, -2)$, then which one of the following is a vertex of this rhombus?

asked Mar 21, 2017 by meena.p

1 answer

If a curve $y = f(x)$ passes through the point $(1, -1)$ and satisfies the differential equation,$y(1 + xy) dx = x dy,$ then $f\bigg(\large\frac{-1}{2}\bigg)$ is equal to :

asked Mar 20, 2017 by meena.p

1 answer

The area (in sq. units) of the region $\{(x,y):y^2 \leq 2x $ and $ x^2+y^2 \geq 4x, x \leq 0, y \geq 0 \} $ is

asked Mar 20, 2017 by meena.p

1 answer

$\lim_\limits{n \to \infty} \bigg( \large\frac{(n-1)(n+2)....3n}{n^{2n}}\bigg)^{1/n}$ is eaual to

asked Mar 20, 2017 by meena.p

1 answer

The integral $\int \large\frac{2x^{12} +5x^{9}}{(x^2+x^3+1)^3}$$dx$ is equal to

asked Mar 17, 2017 by meena.p

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