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A pipe of length 85 cm is closed from one end .Find the number of possible natural oscillations of air column in the pipe whose frequencies lie below 1250 Hz. The velocity of sound in air is 340 m/s .

asked Apr 30, 2014 by yamini.v

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A particle moves with simple harmonic motion in a straight line . In first $\;\tau\;s\;$ after starting from rest it travels a distance a , and in next $\;\tau\;s\;$ it travels 2a , in same direction , then :

asked Apr 30, 2014 by yamini.v

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An open glass tube is immersed in mercury in such a way that a length of 8 cm extends above the mercury level .The open end of the tube is then closed and sealed and the tube is raised vertically up by additional 46 cm .What will be the length of the air column above mercury in the tube now ? (Atmospheric pressure = 76 cm of Hg)

asked Apr 30, 2014 by yamini.v

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One mole of diatomic ideal gas undergoes a cyclic process ABC as shown in figure . The pr ocess BC is adiabatic . The temperatures at A ,B and C are 400 K , 800 K and 600 K respectively .Choose the correct statement :

asked Apr 30, 2014 by yamini.v

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Three rods of Copper , Brass and Steel are welded together to form a Y - shaped structure . Area of cross - section of each rod = $\;4\;cm^{2}\;$ .End of copper rod is maintained at $\;100^{0}C\;$ where as ends of brass and steel kept at $\;0^{0}C\;$ .Lengths of the copper ,brass and steel rods are 46,13 and 12 cms respectively . The rods are thermally insulated from surroundings expect at ends . Thermal conductivities of copper , brass and steel are 0.92 , 0.26 and 0.12 CGS units respectively . Rate of heat flow through copper rod is :$\;\tau$

asked Apr 30, 2014 by yamini.v

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On heating water, bubbles being formed at the bottom of the vessel detatch and rise . Take the bubbles to be spheres of radius R and making a circular contact of radius r with the bottom of the vessel . If r << R , and the surface tension of water is T , value of r just before bubbles detatch is : (density of water is $\;\rho_{w}$)

asked Apr 29, 2014 by yamini.v

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There is a circular tube in a vertical plane . Two liquids which do not mix and of densities $\;d_{1}\;$ and $\;d_{2}\;$ are filled in the tube . Each liquid subtends $\;90^{0}\;$ angle at centre . Radius joining their interface makes an angle $\;\alpha\;$ with vertical . Ratio $\;\large\frac{d_{1}}{d_{2}}\;$ is :

asked Apr 29, 2014 by yamini.v

0 answers

The pressure that has to be applied to the ends of a steel wire of length 10 cm to keep its length constant when its temperature is raised by $\;100^{0}C\;$ : (For steel Young's modulus is $\;2 \times 10^{11} Nm^{-2}\;$ and coefficient of thermal expansion $\;1.1 \times 10^{-5} K^{-1}\;$)

asked Apr 29, 2014 by yamini.v

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Four particles each of mass M and equidistant from each other , move along a circle of radius R under the action of their mutual gravitational attraction . The speed of each particle is :

asked Apr 29, 2014 by yamini.v

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A bob of mass m attached to an inextensible string of length / is suspended from a vertical support . The bob rotates in a horizontal circle with an angular speed $\;w\;$ rad/s about the verticle . About the point of suspension :

asked Apr 29, 2014 by yamini.v

1 answer

When a rubber-band is stretched by a distance x ,it exerts a restoring force of magnitude $\;F=ax+bx^{2}\;$ where a and b are constants . The work done in stretching the unstretched rubber-band by L is :

asked Apr 29, 2014 by yamini.v

0 answers

A block of mass m is placed on a surface with a vertical cross selection given by $\;y=\large\frac{x^{3}}{6}\;$ . If the coefficient of the friction is 0.5 , The maximum height above the ground at which the block can be placed without slipping is :

asked Apr 29, 2014 by yamini.v

0 answers

A mass ' m ' is supported by a massless string wound around a uniform hollow cylinder of mass m and radius R . If the string does not slip on the cylinder , with what acceleration will the mass fall on release ?

asked Apr 29, 2014 by yamini.v

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From a tower of height H , a particle is thrown vertically upwards with a speed u . The time taken by the particle , to hit the ground , is n times that taken by it to reach the highest point of its path . The relation between H , u and n is

asked Apr 29, 2014 by yamini.v

0 answers

The current voltage relation of diode is given by $\;(I=e^{\large\frac{1000V}{T}-1})mA\;$ , where the applied voltage V is in volts and the temperature T is in degree kelvin .If a student makes an error measuring $\;\pm0.001 V\;$ while measuring the current of 5 mA at 300 K , what will be the error in the value of current in mA ?

asked Apr 29, 2014 by yamini.v

1 answer

Let A and B be two events such that $P( \bar {P \cup B})=\large\frac{1}{6}$, $P(A \cap B)=\large\frac{1}{4}$ and $P(\bar {A})=\large\frac{1}{4}$, where $\bar {A}$ stands for the complement of the event A. Then the events A and B are :

asked Apr 7, 2014 by meena.p

1 answer

Let PS be the median of the triangle with vertices P(2, 2), Q(6, –1) and R(7, 3). The equation of the line passing through (1, –1) and parallel to PS is

asked Apr 7, 2014 by sreemathi.v

1 answer

Let $a, b, c\; and \;d$ be non-zero numbers. If the point of intersection of the lines $4ax + 2ay + c = 0$ and $5bx+2by+d=0$ lies in the fourth quadrant and is equidistant from the two axes then

asked Apr 7, 2014 by sreemathi.v

1 answer

$\lim\limits_ {x \to 0} \large\frac{\sin (\pi \cos ^2 x) }{x^2}$ is equal to :

asked Apr 7, 2014 by meena.p

1 answer

If $X= \{ 4^n-3n-1:n \in N\}$ and $Y=\{9(n-1):n \in N\}$. Where $N$ is the set of natural numbers , then $X \cup Y $ is equal to

asked Apr 7, 2014 by meena.p

1 answer

The area of the region described by A={$(x,y):(x^2+y^2\leq 1$ and $y^2\leq 1-x$}

asked Apr 7, 2014 by sreemathi.v

1 answer

The locus of the foot of perpendicular drawn from the centre of the ellipse $x^2+3y^2=6$ on any tangent to it is:

asked Apr 7, 2014 by meena.p

1 answer

Let C be the circle with centre at (1, 1) and radius = 1. If T is the circle centred at (0, y) passing through origin and touching the circle C externally, then the radius of T is equal to

asked Apr 7, 2014 by sreemathi.v

1 answer

Three positive numbers form an increasing G.P. If the middle term in this G.P. is doubled, the new numbers are in A.P. Then the common ratio of the G.P. is

asked Apr 7, 2014 by meena.p

1 answer

If $(10)^9+2(11)^1 (10)^8+ 3(11)^7+.....+10(11)^9=k(10)^9,$ then $k$ is equal to

asked Apr 7, 2014 by meena.p

1 answer

Let the population of rabbits surviving at a time $'t'$ be governed by the differential equation $\large\frac{dp(t)}{dt}=\frac{1}{2}$$p(t)-200$ <br> If p(0)= 100, then what is the value of p(t)?

asked Apr 7, 2014 by sreemathi.v

1 answer

The angle between the lines whose direction cosines satisfy the equations $1+m+n=0$ and $1^2=m^2+n^2$ is

asked Apr 7, 2014 by meena.p

1 answer

If $f$ and $g$ are differentiable function in $[0, 1]$ satisfying $f(0)=2 = g(1),g(0)= 0$ and $f(1)=6 $, then for some $c\in [0,1]$

asked Apr 7, 2014 by sreemathi.v

1 answer

The slope of the line touching both the parabolas $y^2 = 4x$ and $x^2 =- 32y$ is

asked Apr 7, 2014 by meena.p

1 answer

If $x=-1$ and $x = 2$ extreme points of $f(x)= \alpha \log |x| +\beta x^2+x$ then

asked Apr 7, 2014 by meena.p

1 answer

If $g$ is the inverse of a function $f$ and $f'(x) =\large\frac{1}{1+x^5}$, then $g'(x)$ is equal to

asked Apr 7, 2014 by meena.p

1 answer

Let $\alpha$ and $\beta$ be the roots of equation $px^2 +qx+r=0,p\neq 0.$If p,q,r are in A.P.and $\large\frac{1}{\alpha}+\frac{1}{\beta}$$=4$,then the value of $\mid\alpha-\beta\mid$ is

asked Apr 7, 2014 by sreemathi.v

1 answer

Assume that an electric field $\bar {E}=30x^2 \hat i$ exists in space. Then the potential difference $V_A - V_O$ , where $V_O$ is the potential at the origin and $V_A$ the potential at $x = 2$ $m$ is :

asked Apr 7, 2014 by meena.p

1 answer

Two beams, $A$ and $B$, of plane polarized light with mutually perpendicular planes of polarization are seen through a polaroid. From the position when the beam $A$ has maximum intensity (and beam $B$ has zero intensity), a rotation of polaroid through $30^{\circ}$ makes the two beams appear equally bright. If the initial intensities of the two beams are $I_A$ and $I_B$ respectively, then $\large\frac{I_A}{I_B}$ equals :

asked Apr 7, 2014 by meena.p

1 answer

On heating water, bubbles being formed at the bottom of the vessel detatch and rise. Take the bubbles to be spheres of radius $R$ and making a circular contant fo radius $r$ with the bottom of the vessel. If $r << R$ and the surface tension of water is $T$, value of $r$ just before bubbles detatch is : (density of water is $\rho_w$ )

asked Apr 7, 2014 by meena.p

1 answer

The most suitable reagent for the conversion of $R-CH_2 -OH\rightarrow R-CHO$ is

asked Apr 7, 2014 by sreemathi.v

1 answer

When a rubber-band is stretched by a distance $x$, it exerts a restoring force of magnitude $F=ax+bx^2$ where $a$ and $b$ are constants. The work done in stretching the unstretched rubber-band by $L$ is :

asked Apr 7, 2014 by meena.p

1 answer

For complete combustion of ethanol $C_2H_5OH(l)+3O_2(g)\rightarrow 2CO_2(g)+3H_2O(l)$ the amount of heat produced as measured in bomb calorimeter,is 1$364.47\; kJ mol^{–1}$ at $25^{\large\circ}C$.Assuming ideality the Enthalpy of combustion,$\Delta_eH$,for the reaction will be: $(R = 8.314 kJ mol^{–1}$)

asked Apr 7, 2014 by sreemathi.v

1 answer

A block of mass $m$ is placed on a surface with a vertical cross section given by $y=\large\frac{x^3}{6}$. If the coefficient of friction is $0.5$, the maximum height above the ground at which the block can be placed without slipping is :

asked Apr 7, 2014 by meena.p

1 answer

The radiation corresponding to $3 \to 2$ transition of hydrogen atom falls on a metal surface to produce photoelectrons. These electrons are made to enter a magentic field of $3 \times 10^{-4}T$ . If the radius of the largest circular path followed by these electrons is $10.0\; mm$, the work function of the metal is close to :

asked Apr 7, 2014 by meena.p

1 answer

Among the following oxoacids, the correct decreasing order of acid strength is

asked Apr 7, 2014 by sreemathi.v

1 answer

Hydrogen $\bigg( _1H^1\bigg)$, Deuterium $\bigg(_1H^2 \bigg)$, singly ionised Helium $\bigg(_2He^{4}\bigg)^+$ and doubly ionised . Consider an electron transition from $n = 2$ to $n = 1$. If the wave lengths of emitted radiation are $\lambda _1, \lambda_2, \lambda_3\;and \;\lambda_4$ respectively then approximately which one of the following is correct?

asked Apr 7, 2014 by meena.p

1 answer

Which one is classified as a condensation polymer?

asked Apr 7, 2014 by sreemathi.v

1 answer

The ratio of masses of oxygen and nitrogen in a particular gaseous mixture is 1 : 4. The ratio of number of their molecules is

asked Apr 7, 2014 by sreemathi.v

1 answer

A green light is incident from the water to the air-water interface at the critical angle $(\theta)$ . Select the correct statement

asked Apr 7, 2014 by meena.p

1 answer

Given below are the half - cell reactions\begin{array}{1 1}Mn^{2+}+2e^-\rightarrow Mn;E^{\large\circ}=-1.18V\\2(MN^{3+}+e^-\rightarrow Mn^{2+});E^{\large\circ}=-1.18V\end{array}The $E^{\large\circ}$ for $3Mn^{2+}\rightarrow Mn+2Mn^{3+}$ will be

asked Apr 7, 2014 by sreemathi.v

1 answer

The major organic compound formed by the reaction of 1, 1, 1 - trichloroethane with silver powder is

asked Apr 7, 2014 by sreemathi.v

1 answer

The correct set of four quantum numbers for the value electrons of rubidium atom (Z = 37) is

asked Apr 7, 2014 by sreemathi.v

1 answer

There is a circular tube in a vertical plane. Two liquids which do not mix and of densities $d_1$ and $d_2$ are filled int hetube. Each liquid subtends $90^{\circ}$ angle at centre. Radius joining there interface makes an angle $\alpha$ with vertical. Ratio $\large\frac{d_1}{d_2}$ is

asked Apr 7, 2014 by meena.p

1 answer

A pipe of length $85\;cm$ is closed from one end. Find the number of possible natural oscillations of air column in the pipe whose frequencies lie below $1250\; Hz$. The velocity of sound in air is $340\; m/s$.

asked Apr 7, 2014 by meena.p

1 answer

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