A to Z Exams

A body 'A' starts from rest with an acceleration 'a1'. After 2 seconds another body 'B' starts from rest with an acceleration a2.If they travel equal distance in the 5th second after the start of 'A'.a1:a2 equal to:

In Youngs double slit experiment the separation between the slits is halved and the distance between the slits and screen is doubled .The fringe width is

Two long straight conductors are held parallel to each other at a distance 0.3m.If the conductors carry currents 2A and 8A in opposite directions,the distance of the neutral point from the conductor carrying smaller current is

The liquids at temperature 600C and 300C respectively have masses in the ratio 3 : 4 and their specific heats in the ratio 4 : 5. If the two liquids are mixed, the resultant temperature is:

A man 50 kg is standing at one end on a boat of length 25 m and mass 200 kg. If he starts running and when he reaches the other end, he has a velocity 2 ms-1 with respect to the boat.The final velocity of the boat is : (in ms-1)

A 25 watt,220 volt bulb and a 100 watt,220 volt bulb are connected in series across 440 volt line

An ideal transformer has 400turns in the primary and 200 turns in the secondary.If the primary is connected to a 12 V battery,then the secondary voltage is

The equation of wave is y=10cos2π((t/0.02)-(x/10)),where ‘t’ is in seconds an x in cm.The phase difference between two points separated by a distance of 5cm at any instant is

A wire of length 44cm is bent into a circle and a current of 9.8A is passed through it.The intensity of magnetic induction at the centre of the circle is

The frequency of transverse vibrations in a stretched string is 200 Hz.If the tension is increased 4 times and the length is reduced to one fourth the original values,the frequency of vibrations will be

The coils in two moving coil galvanometer have their areas in the ratio of 2:3 and number of turns in the ratio 4:5. These two coils carry the same current and are situated in the same field. The deflections produced by these coil will be in the ratio of

An air bubble of radius 1 cm rises from the bottom portion through a liquid of density 1.5 g/cc at a constant speed of 0.25 cms-1. If the density of air is neglected, the coefficient of viscosity of the liquid is approximately, (In Pas) :

A prism of refractive index μ and angle A is placed in the minimum deviation position. If the angle of minimum deviation Is A, then the value of A in terms of μ is

A motor cycle starts from rest and accelerates along a straight path at 2m/s2.At the starting point of the motor cycle, there is a stationary electric siren. How far has the motor cycle gone when the driver hears the frequency of the siren at 94% of its value when the motor cycle was at rest?(speed of sound=330ms-1)

Two solid spheres (A and B) are made of metals of different densities and ρA  and ρB  respectively. If their masses are equal, the ratio of their moments of inertia {IB/IA) about their respective diameter is

A pipe having an internal diameter ‘D’ is connected to anther pipe of same size. water flows into the second pope through ‘n’ holes, each of diameter ‘d’. If the water in the first pipe has speed ‘V’, the speed of water leaving the second pipe is

A photo-cathode is irradiated in turn by light of wavelengths 4000 A0 and 6200 A0 respectively. The ratio of the stopping potentials in the two cases is found to be 2:1. The work function of the photo-cathode is nearly

An open pipe resonates to a frequency ‘f1’ and a closed pipe resonates to a frequency ‘f2’.If they are joined together to form a longer tube,then it will resonate to a frequency of(neglect end corrections)

a spark is produced between two insulated surfaces maintained at a potential difference of 5 x 106 volt. The energy output is 10-5 J. The charge transferred during the spark is

A first order reaction has commenced with 0.2M solution of the reactants. If the molarity of the solution falls to 0.02M after 100 minutes the rate constant of the reaction is

When two unknown resistances are placed in the gaps of meterbridge,the null point is found to be 40cm from one end of the bridge wire.when one of the resistances is shunted with a 10 ohm coil,the null points is 25cm form the same end.The value of each of the unknown resistances is

Three condensers 1μF,2μF and 3μF are connected in series to a p.d of 330volt.The PD across the plates of 3μF is

When a high resistance R is connected in series with a voltmeter of resistance G, the range of the voltmeter increases 5 times. Then G:R will be

The speed of transverse vibrations in a stretched string is 700cm/s.If the string is 2m long,the frequency with which it resonates in fundamental mode is

The frequency of the sound of a car horn as recorded by an observer towards whom the car is moving differs from the frequency of the horn by 10%.Assuming the velocity of sound in air to be 330ms-1,the velocity of the car is

A soap bubble of radius r is blown up to form a bubble of radius 2r under isothermal conditions. If T is the surface tension of soap solution, the energy spent in the blowing

One mole of a gas occupies 100 ml at 50 mm pressure.The volume of 2 mole of the gas at 100 mm pressure and same temperature is

A 2 MeV proton is moving perpendicular to a uniform magnetic field of 2.5 tesla. The force on the proton is (mass of proton = 1.6 x 10-27 kg)

When a liquid in a glass vessel, is heated its apparent expansion is 10.30 x 10-4same liquid when heated in a metal its apparent expansion 10.06 x 10-4/0C. The coefficient of linear expansion of the metal is : (coefficient of linear expansion of glass = 9 x 10-6/0C):

A glass tube 1.5m long and open at both ends, is immersed vertically in a water tank completely. A tuning fork of 600Hz is vibrated and kept at the upper end of tube and tube is gradually raised out of water.The total number of resonances heard before when the tube comes out of water, taking velocity of sound as 330m/sec. is

A straight wire of length 0.5 metre and carrying a current of 1.2 ampere is placed in a uniform magnetic field of induction 2 tesla.If the magnetic field is perpendicular to the length of the wire,the force acting on the wire

A rifle of 20 kg mass can fire 4 bullets per second. The mass of each bullet is 35 x 10-3 kg and its final velocity is 400 ms-1. Then what force must be applied on the rifle so that it does not move backwards while firing the bullets

In youngs experiment λ=4000A0 fringes observed have a width β. The light illuminating with new λ=6000A0 and the separation between the interfering sources is halved. The ratio of the distance between the screen and the interfering sources if the fringe width remains unaltered respectively is

Under minimum deviation condition in a prism, if a ray is incident at an angle of 300. The angle between the emergent ray and the second refracting surface of the prism is: ( Angle of prism = 600)

If a is the radius of first Bohr orbit in hydrogen atom, the radius of 3rd orbit is :

The fundamental physical quantities that have same dimensions in the dimensional formula of torque and angular momentum are

A charge of 4 μC is placed in a uniform electric field of intensity 100N/C. The force acting on the charge is

The two lenses of an achromatic doublet should have

A galvanometer of resistance 20Ω is to be shunted so that only 1% of the current passes through it.shunt connected is

In n-p-n transistor, in CE configuration:(1)  The emitter is heavily doped than the collector.(2)  Emitter and collector can be interchanged.(3)  The base region is very thin but is heavily doped.(4)  The conventional current flows from base to emitter

X-rays of energy 50 KeV are scattered from a carbon target. The scattered rays are detected at 900 from the incident beam. the percentage change in wave length approximately [mo=9.0x10-31kg, c=3x108 m/sec] is

A charge of 10 units is divided so that force between the two charges is maximum when placed 2cm apart. The two charges are

The direction of the magnetic field produced by straight current carrying conductor is given by

The magnetic induction at point 1cm away from a straight long current carrying Conductor is found to be 1x10-5wb/m2.the current that is passing through the conductor is

When an air bubble of radius r rises from the bottom to the surface of a lake. Its radius becomes 5r/4 (the pressure of the atmosphere is equal to the 10 m height to water column). If the temperature is constant and the surface tension is neglected the depth of the lake is

A circular coil of radius 11cm,carries and current of 2.5 amperes.If it has 700 turns,the flux density at the centre of the coil is

The wavelength of blue light in air is 45000A if the refractive index for blue light is 1.55 in glass what will be the wavelength of blue light in glass(c=3x108m/s)its frequency is

The neutral temperature of a thermo couple is5000C.If cold junction is at 300C the inversion temperature is

A machine gun fires 360 bullets per minute. Each bullet moves with a velocity of 600ms-1, If the power of the gun is 5.4kw, the mass of each bullet is,

Two bodies of 6 kg and 4 kg masses have their velocity   5i^-2j^+10k^   and   10i^-2j^+5k^ respectively. Then the velocity of their centre of mass is

In a hall a person receives direct sound from a source 120m away. He also receives waves from the same source which reach him after being reflected from the 25m high ceiling at a point midway between them. The two waves interfere constructively for wavelengths (in metre) of

7N14+2He4→X+1H1 then ‘X’ is

A constant voltage of 25 V is applied to a series L-R circuit at t = 0, by closing a switch. What is the potential difference across the resistor and the inductor at time t = 0

The radioactivity of a sample is 'X' at a time 't1' and ‘Y’ at a time 't2'. If the mean life time of the specimen is г the number of atoms that have disintegrated in the time interval (t1 – t2) is

An electric current passes through a long straight wire. At a distance 5cm from the wire, the magnetic field is B. The field at 20cm from the wire would be:

A train is travelling at 120kmph and blows a whistle of frequency 1000Hz.The frequency of the note heard by a stationary observer if the train is approaching him and moving away from him are(Velocity of sound in air=330ms-1)nearly

When cold junction is at 00C variation of thermo emf(e) of Fe-Cu thermo couple with temperature of hot junction t is given as e=14t-0.02t2.Its neutral temperature is

The force acting on a charge of 10-10C placed in an electric field of intensity 600 V/m is

A car with a horn of frequency 620 Hz, travels towards a large wall with a speed 20 m/s. If velocity of sound of 330 m/s the frequency of echo of sound of horn as heard by driver

Which of the following statements is not true in the case of 1 Huygen's eye piece

A bomb is dropped from an aircraft travelling horizontally at 150m/s at a height of 490m. The horizontal distance travelled by the bomb before it hits the ground is (in metre):

Particles and their anti-particles have

A coil has an inductance of 0.05H and 100 turns and 0.02A current is passed through it. Flux linked with coil is

In Resonance Column experiment with a closed pipe, the first, second and third reso-nance lengths L1, L2, L3 respectively beat the relationship

Two ions having masses in the ratio 1:1 and charges 1 : 2 are projected into uniform magnetic field perpendicular to the field with speeds in the ratio 2:3. The ratio of the radii of circular paths along with the two particles move is

when a wave traverses a medium , the displacement of a particle located at 'x' at a time  't' is given by  y=a sin (bt - cx) , where a,b and c are constants of the wave , which of the following is a quantity with dimensions

Consider the two following statements A and B,and identify the correct choice given in the answers:A) In photovoltaic cells the photoelectric current produced is not proportional to the Intensity of Incident light (B) In gas filled photo emissive cells, the velocity of photo-electrons depends on the wavelength of the incident radiation

if the length of a stretched string is shortened by 40% and the tension is increased by 44%,then the ratio of the final and initial fundamental frequencies is

Along straight conductor carrying a current of 2A is in parallel to another conductor of length 5 cm and carrying a current 3A. They are separated by a distance of 10cm B due to first conductor at second conductor is

A man stands infront of a hill rock and fires a gun. He hears an echo after 1.5 sec. the distance of the hill rock form the man is (velocity of sound in air = 330m/s)

Two charges 8C and -6C are placed at a distance of separation d between them and exerts a force of magnitude  F on each other. If a charge 8C is added to each of these and they are brought nearer to by a distance d/3, the magnitude of force between them

Photoelectric current can be increased by using :

Two bar magnets A, B are placed one over the other and are allowed to vibrate in a vibration magnetometer. They make 20 oscillations per minute when the similar poles of A and B are on the same side, while they make 15 oscillations per minute when their opposite poles lie on the same side. If MA and MB are the magnetic moments of A and B and if MA > MB, the ratio of MA and MB is

An ammeter whose resistance is 180 Ω shows full scale deflection when the current is 2mA.The shunt required to convert into an ammeter reading 20 mA is (in ohm)

The number of turns in primary and secondary coils of a transformer is 50 and 200. If the current in the primary coil is 4 A, then the current in the secondary coil is

An iron block of sides 50 cm x 8 cm x 15 cm has to be pushed along the floor. The force required will be minimum when the surface in contact with ground is:

If a body is in equilibrium under a set of non-collinear forces, the minimum number of forces has to be

Two wires A and B are of lengths 40 cm and 30 cm, A is bent into a circle of radius r and B into an arc of radius r. A current i1 passed.through A and i2 through B. To have the same magnetic inductions at the centre, the ratio of    i1  :   i2  is

Two tuning forks A and B produce 6 beats per second when sounded together. When B is slightly loaded with wax the beats are reduced to 4 per second. If the frequency of A is 512 Hz the frequency of B is

One of the refracting surface of a prism of angle 300 is silvered. A ray of light incident at angle of 600 retraces its path. The refractive index of the material of a prism is

A 1.0 HP IP motor pumps out water from a well of 30m and fills water tank of volume 2238 litres at a height of 10 m from the ground. The running time of the motor to fill the empty water tank is: (g= 10 ms-2)

A cell of emf 2V and negligible resistance is connected in series with a resistance of 5 Ω, and a potentiometer wire of resistance 10 ohm. What is the potential drop per cm if the length of the potentiometer wire is 10 m. The emf a cell which is balanced by 750 cm long wire is

If the angle of a prism is 600 and angle of minimum deviations is 400, then the angle of refraction in the prism will be

The pole strength of a 12 cm long bar magnet is 2.0 A-m. The magnetic induction at a point 10 cm away from the centre of the magnet on the axial line is (μ0/4∏=10-7Hm-1)

The potential energy of a proton is 3.2x10-18J at a particular point. The electric potential at this point is

The emf of a Cu-Fe thermocouple varies with the temperature T of the hot junction, the cold junction being at 100C, as Vinμv=14T-0.02T2.Determinate the neutral temperature and the of inversion.

A potentiometer wire of length 100 cm has a resistance of 10 Ω. It is connected in series with a resistance and a cell of emf 2V and of negligible internal resistance. A source of emf 10 mV is balanced against a length of 40 cm of the potentiometer wire. The value of external resistance is:

A 4 μF capacitor is charged by a 200V battery. It is then dis-connected from the supply and is connected to another uncharged 2 μF capacitor. During the process, loss of energy (in J) is

The displacement of a particle moving in a straight line is given by x = 2t2+t+5 where x is expressed in meter and 't' in second.The acceleration at t = 2sec is

A force is experienced by cathode rays when they pass through uniform electric field

A pipe of length l1 closed at one end is kept in a chamber of gas of density ρ1.A second pipe open at both ends is placed in a second chamber of gas of density ρ2.The compressibility of both.The gases is equal.If frequency of first overtone in both the cases is equal,the length of the second pipe is

Two unknown resistance X and Y are connected to left and right gaps of a meter bridge and the balancing point is obtained at 80 cm from left. When a 10Ω resistance is connected in parallel to X, the balance point is 50 cm from left. The values of X and Y respectively are

The maximum tension a rope can withstand is 60 kg wt The ratio of maximum acceleration with which two boys of masses 20 kg and 30 kg can climb up the rope at the same time is

Two point charges -q and +q are located at points (0, 0, -a) and (0, 0, a) respectively. The electric potential at a point (0, 0, z), where z > a

A rod with linear charge density λ is bent in the shape of circular ring.The electric potential at the centre of the circular ring is

The elementary particles heavier than nucleons are called

If the focal length of a lens for marginal rays and paraxial rays are 12.5cm and 13cn respectively, the longitudinal spherical aberration is

A metal string is fixed between rigid supports. It is initially at negligible tension. Its youngs modulus is ‘Y’ density is ρ and coefficient of linear expansion is α. It is now cooled through a temperature ‘t’ transverse waves will move along it with a speed.

In the Young's double slit experiment, the intensities at two points P1, and P2 on the screen are respectively I1, and I2. If P1, is located at the centre of a bright fringe and P2 is located at a distance equal to a quarter of fringe width from P1 then I1/I2 is

A cell of emf 2V and negligible resistance is connected in series with a resistance of 5 ohm,and a potentiometer wire of resistance 10 ohm.what is the potential drop per cm if the length of the potentiometer wire is 10m.The emf of a cell which is balanced by 750cm long wire is