AIEEE 2004

In a \(LCR\) circuit capacitance is changed from \(C\) to \(2\) \(C\). For the resonant frequency to remain unchaged, the inductance should be changed from \(L\) to

In an \(LCR\) series \(a.c.\) circuit, the voltage across each of the components, \(L,C\) and \(R\) is \(50V\). The voltage across the \(L.C\) combination will be :

Alternating current can not be measured by \(D.C.\) ammeter because

The binding energy per nucleon of deuteron \(\left( {{}_1^2\,H} \right)\) and helium nucleus \(\left( {{}_2^4\,He} \right)\) is \(1.1\) \(MeV\) and \(7\) \(MeV\) respectively. If two deuteron nuclei react to form a single helium nucleus, th...

An \(\alpha\)-particle of energy \(5\) \(MeV\) is scattered through \({180^ \circ }\) by a fixed uranium nucleus. The distance of closest approach is of the order of

A nucleus disintegrated into two nuclear parts which have their velocities in the ratio of \(2:1.\) The ratio of their nuclear sizes will be

A machine gun fires a bullet of mass \(40\) \(g\) with a velocity \(1200m{s^{ - 1}}.\) The man holding it can exert a maximum force of \(144\) \(N\) on the gun. How many bullets can he fire per second at the most?

Which of the following statements is FALSE for a particle moving in a circle with a constant
angular speed?

An electric current is passed through a circuit containing two wires of the same material, connected in parallel. If the lengths and radii are in the ratio of \({4 \over 3}\) and \({2 \over 3}\), then the ratio of the current passing throu...

In a meter bridge experiment null point is obtained at \(20\) \(cm\), from one end of the wire when resistance \(X\) is balanced against another resistance \(Y.\) If \(X < Y\), then where will be the new position of the null point from the...

A material \('B'\) has twice the specific resistance of \('A'.\) A circular wire made of \('B'\) has twice the diameter of a wire made of \('A'\). Then for the two wires to have the same resistance, the ratio \({l \over B}/{l \over A}\) of ...

Thermistors are usually made of

The resistance of the series combination of two resistances is \(S.\) When they are jointed in parallel the total resistance is \(P.\) If \(S = nP\) then the Minimum possible value of \(n\) is

The Kirchhoff's first law \(\left( {\sum i = 0} \right)\) and second law \(\left( {\sum iR = \sum E} \right),\) where the symbols have their usual meanings, are respectively based on

The electrochemical equivalent of a metal is \({3.35109^{ - 7}}\) \(kg\) per Coulomb. The mass of the metal liberated at the cathode when a \(3A\) current is passed for \(2\) seconds will be

The thermo \(emf\) of a thermocouple varies with temperature \(\theta\) of the hot junction as \(E = a\theta + b{\theta ^2}\) in volts where the ratio \(a/b\) is \({700^ \circ }C.\) If the cold junction is kept at \({0^ \circ }C,\) then ...

The total current supplied to the circuit by the battery is

According to Einstein's photoelectric equation, the plot of the kinetic energy of the emitted photo electrons from a metal \(Vs\) the frequency, of the incident radiation gives as straight the whose slope

The work function of a substance is \(4.0\) \(eV.\) The longest wavelength of light that can cause photo-electron emission from this substance is approximately.

In a uniform magnetic field of induction \(B\) a wire in the form of a semicircle of radius \(r\) rotates about the diameter of the circle with an angular frequency \(\omega .\) The axis of rotation is perpendicular to the field. If the tot...

A metal conductor of length \(1\) \(m\) rotates vertically about one of its ends at angular velocity \(5\) radians per second. If the horizontal component of earth's magnetic field is \(0.2 \times {10^{ - 4}}T,\) then the \(e.m.f.\) develo...

A coil having \(n\) turns and resistance \(R\Omega\) is connected with a galvanometer of resistance \(4R\Omega .\) This combination is moved in time \(t\) seconds from a magnetic field \({W_1}\) weber to \({W_2}\) weber. The induced curren...

An electromagnetic wave of frequency \(v=3.0\) \(MHz\) passes from vacuum into a dielectric medium with permittivity \(\in = 4.0.\) Then

A radiation of energy \(E\) falls normally on a perfectly reflecting surface. The momentum transferred to the surface is

When \(npn\) transistor is used as an amplifer

For a transistor amplifier in common emitter configuration for load impedance of \(1k\,\Omega\) \(\left( {{h_{fe}} = 50} \right.\) and \(\left. {{h_{oe}} = 25} \right)\) the current gain is

A piece of copper and another of germanium are cooled from room temperature to \(77K,\) the resistance of

The manifestation of band structure in solids is due to

When \(p\)-\(n\) junction diode is forward biased then

A charged oil drop is suspended in a uniform field of \(3 \times {10^4}\) \(v/m\) so that it neither falls nor rises. The charge on the drop will be (Take the mass of the charge \(= 9.9 \times {10^{ - 15}}\,\,kg\) and \(g = 10\,m/{s^2}\))...

Two spherical conductors \(B\) and \(C\) having equal radii and carrying equal charges on them repel each other with a force \(F\) when kept apart at some distance. A third spherical conductor having same radius as that \(B\) but uncharged ...

Four charges equal to -\(Q\) are placed at the four corners of a square and a charge \(q\) is at its center. If the system is in equilibrium the value of \(q\) is

A charge particle \('q'\) is shot towards another charged particle \('Q'\) which is fixed, with a speed \('v'\). It approaches \('Q'\) upto a closest distance \(r\) and then returns. If \(q\) were given a speed of \('2v'\) the closest dista...

A light ray is incident perpendicularly to one face of a \({90^ \circ }\) prism and is totally internally reflected at the glass-air interface. If the angle of reflection is \({45^ \circ }\), we conclude that the refractive index \(n\)

A plano convex lens of refractive index \(1.5\) and radius of curvature \(30\) \(cm\). Is silvered at the curved surface. Now this lens has been used to form the image of an object. At what distance from this lens an object be placed in ord...

If \(g\) is the acceleration due to gravity on the earth's surface, the gain in the potential energy of an object of mass \(m\) raised from the surface of the earth to a height equal to the radius \(R\) of the earth is

The time period of an earth satellite in circular orbit is independent of

A satellite of mass \(m\) revolves around the earth of radius \(R\) at a height \(x\) from its surface. If \(g\) is the acceleration due to gravity on the surface of the earth, the orbital speed of the satellite is

Suppose the gravitational force varies inversely as the nth power of distance. Then the time period of a planet in circular orbit of radius \(R\) around the sun will be proportional to

The temperature of the two outer surfaces of a composite slab, consisting of two materials having coefficients of thermal conductivity \(K\) and \(2K\) and thickness \(x\) and \(4x,\) respectively, are \({T_2}\) and $${T_1}\left( {{T_2} > {...

If the temperature of the sun were to increase from \(T\) to \(2T\) and its radius from \(R\) to \(2R\), then the ratio of the radiant energy received on earth to what it was previously will be

Which of the following statements is correct for any thermodynamic system ?

One mole of ideal monatomic gas \(\left( {\gamma = 5/3} \right)\) is mixed with one mole of diatomic gas \(\left( {\gamma = 7/5} \right)\). What is \(\gamma\) for the mixture? \(\gamma\) Denotes the ratio of specific heat at constant pr...

Time taken by a \(836\) \(W\) heater to heat one litre of water from \(10{}^ \circ C\) to \(40{}^ \circ C\) is

Two thermally insulated vessels \(1\) and \(2\) are filled with air at temperatures \(\left( {{T_1},{T_2}} \right),\) volume \(\left( {{V_1},{V_2}} \right)\) and pressure \(\left( {{P_1},{P_2}} \right)\) respectively. If the value joining t...

A block rests on a rough inclined plane `making an angle of \({30^ \circ }\) with the horizontal. The coefficient of static friction between the block and the plane is \(0.8.\) If the frictionless force on the block is \(10\) \(N,\) the mas...

Two masses \({m_1} = 5kg\) and \({m_2} = 4.8kg\) tied to a string are hanging over a light frictionless pulley. What is the acceleration of the masses when left free to move? \(\left( {g = 9.8m/{s^2}} \right)\)

The materials suitable for making electromagnets should have

Curie temperature is the temperature above which

The length of a magnet is large compared to its width and breadth. The time period of its oscillation in a vibration magnetometer is \(2s.\) The magnet is cut along its length into three equal parts and these parts are then placed on each o...