NEET 2013 Physics Paper

The primary of a transformer when connected to a dc battery of 10 Volt draws a current of 1 mA. The number of turns of the primary and secondary windings are 50 and 100 respectively. The voltage in the secondary and the current drawn by the circuit in the secondary are respectively

A coil of self-inductance L is connected in series with a bulb B and an AC source. Brightness of the bulb decreases when

An electron in hydrogen atom makes a transition n1 $\to$ n2 where n1 and n2 are principal quantum numbers of the two states. Assuming Bohr's model to be valid, the time period of the electron in the initial state is eight times that in the final state. The possible values of n1 and n2 are

Ratio of longest wave lengths corresponding to Lyman and Balmer series in hydrogen spectrum is

The internal resistance of a 2.1 V cell which gives a current of 0.2 A through a resistance of 10 $\Omega$ is

A 12 cm wire is given a shape of a right angled triangle ABC having sides 3 cm, 4 cm and 5 cm as shown in the figure. The resistance between two ends (AB, BC, CA) of the respective sides are measured one by one. Their ratio is

Ten identical cells connected in series are needed to heat a wire of length one meter and radius 'r' by 10oC in time 't'. How many cells will be required to heat the wire of length two meter of the same radius by the same temperature in time 't'?

A wire of resistance 4 $\Omega$ is stretched to twice its original length. The resistance of stretched wire would be

Two rods are joined end to end, as shown. Both have a cross-sectional area of 0.01 cm2. Each is 1 $-$6

meter long. One rod is of copper with a resistivity of 1.7 $\times$ 10 ohm-centimeter, the other is of iron $-$5

with a resistivity of 10 ohm-centimeter.

How much voltage is required to produce a current of 1 ampere in the rods?

The resistances of the four arms P, Q, R and S in a Wheatstone's bridge are 10 ohm, 30 ohm, 30 ohm and 90 ohm, respectively. The e.m.f. and internal resistance of the cell are 7 volt and 5 ohm respectively. If the galvanometer resistance is 50 ohm, the current drawn from the cell will be

A parallel beam of fast moving electrons is incident normally on a narrow slit. A fluorescent screen is placed at a large distance from the slit. If the speed of the electrons is increased, which of the following statements is correct?

The de-broglie wavelength of neutrons in thermal equilibrium at temperature T is

The wavelength $\lambda$e of an electron and $\lambda$p of a photon of same energy E are related by

For photoelectric emission from certain metal the cutoff frequency is $v$. If radiation of frequency 2$\nu$ impinges on the metal plate, the maximum possible velocity of the emitted electron will be (m is the electron mass)

A source of light is placed at a distance of 50 cm from a photo cell and the stopping potential is found to be V0. If the distance between the light source and photo cell is made 25 cm, the new stopping potential will be:

A wire loop is rotated in a magnetic field. The frequency of change of direction of the induced e.m.f. is

A current of 2.5 A flows through a coil of inductance 5 H. The magnetic flux linked with the coil is

The condition under which a microwave oven heats up a food item containing water molecules most efficiently is

An electromagnetic wave of frequency $\nu = 3.0$ MHz passes from vaccum into a dielectric medium with relative permittivity $\varepsilon_r$ = 4.0. Then

A charge q is placed at the centre of the line joining two equal charges Q. The system of the three charges will be in equilibrium if q is equal to

Two pith balls carrying equal charges are suspended from a common point by strings of equal length, the equilibrium separation between them is r. Now the strings are rigidly clamped at half the height. The equilibrium separation between the balls now becomes

An electric dipole of dipole moment p is aligned parallel to a uniform electric field E. The energy required to rotate the dipole by 90o is

A, B and C are three points in a uniform electric field. The electric potential is

A fluid is in streamline flow across a horizontal pipe of variable area of cross section. For this which of the following statements is correct?

The radius of a planet is twice the radius of earth. Both have almost equal average mass densities. VP and VE are escape velocities of the planet and the earth, respectively, then

A particle of mass 'm' is kept at rest at a height 3R from the surface of earth, where 'R' is radius of earth and 'M' is mass of earth. The minimum speed with which it should be projected, so that it does not return back, is

(g is acceleration due to gravity on the surface of earth)

A body of mass 'm' is taken from the earth's surface to the height equal to twice the radius (R) of the earth. The change in potential energy of body will be

Infinite number of bodies, each of mass 2 kg are situated on x-axis at distance 1 m, 2 m, 4 m, 8 m,..., respectively, from the origin. The resulting gravitational potential due to this system at the origin will be

In a vessel, the gas is at pressure P. If the mass of all the molecules is halved and their speed is doubled, then the resultant pressure will be

A car is moving in a circular horizontal track of radius 10 m with a constant speed of 10 m/s. A bob is suspended from the roof of the car by a light wire of length 1.0 m. The angle made by the wire with the vertical is

Three blocks with masses m, 2m and 3m are connected by strings, as shown in the figure. After an upward force F is applied on block m, the masses move upwards at constant speed v. What is the net force on the block of mass 2m? (g is the acceleration due to gravity)

The upper half of an inclined plane of inclination $\theta$ is perfectly smooth while lower half is rough. A block starting from rest at the top of the plane will again come to rest at the bottom, if the coefficient of friction between the block and lower half of the plane is given by

A bar magnet of length $'l'$ and magnetic dipole moment 'M' is bent in the form of an arc as shown in figure. The new magnetic dipole moment will be

A bar magnet of magnetic moment M is placed at right angles to a magnetic induction B. If a force F is experienced by each pole of the magnet, the length of the magnet will be

A current loop in a magnetic field

If the ratio of diameters, lengths and Young's modulus of steel and copper wires shown in the figure are p, q and s respectively, then the corresponding ratio of increase in their lengths would be

The following four wires are made of the same material. Which of these will have the largest extension when the same tension is applied?

A stone falls freely under gravity. It covers distances h1, h2 and h3 in the first 5 seconds, the next 5 seconds and the next 5 seconds respectively. The relation between h1, h2 and h3 is

The displacement 'x' (in meter) of a particle of mass 'm' (in kg) moving in one dimension under the action of a force, is related to time 't' (in sec) by t = $\sqrt{x} + 3$. The displacement of the particle when its velocity is zero, will be

A circular coil ABCD carrying a current 'i' is placed in a uniform magnetic field. If the magnetic force on the segment AB is $\vec{F}$, the force on the remaining segment BCDA is

A long straight wire carries a certain current and produces a magnetic field 2 $\times$ 10$-$4 Wb m${}^{-2}$ at a perpendicular distance of 5 cm from the wire. An electron situated at 5 cm from the wire moves with a velocity 107 m/s towards the wire along perpendicular to it. The force experienced by the electron will be (charge on electron 1.6 $\times$ 10$-$19 C)

When a proton is released from rest in a room, it starts with an initial acceleration $a$0 towards west. When it is projected towards north with a speed $v$0 it moves with an initial acceleration 3$a$0 towards west. The electric and magnetic fields in the room are

The half life of a radioactive isotope 'X' is 20 years. It decays to another element 'Y' which is stable. The two elements 'X' and 'Y' were found to be in the ratio 1: 7 in a sample of a given rock. The age of the rock is estimated to be

How does the Binding Energy per nucleon vary with the increase in the number of nucleons?

A certain mass of Hydrogen is changed to Helium by the process of fusion. The mass defect in fusion reaction is 0.02866 u. The energy liberated per u is (given 1 u = 931 MeV)

$\alpha$-particles, $\beta$-particles and $\gamma$-rays are all having same energy. Their penetrating power in a given medium in increasing order will be

A particle of mass m oscillates along x-axis according to equation x = asin$\omega$t. The nature of the graph between momentum and displacement of the particle is

The velocity of a projectile at the initial point A is $\left(2\hat{i} + 3\hat{j}\right)$ m/s. Its velocity (in m/s) at point B is

A plano convex lens fits exactly into a plano concave lens. Their plane surfaces are parallel to each other. If lenses are made of different materials of refractive indices $\mu$1 and $\mu$2 and R is the radius of curvature of the curved surface of the lenses, then the focal length of the combination is

For a normal eye, the cornea of eye provides a converging power of 40 D and the least converging power of the eye lens behind the cornea is 20 D. Using this information, the distance between the retina and the cornea-eye lens can be estimated to be

Two plane mirrors are inclined at 70°. A ray incident on one mirror at angle, $\theta$ after reflection falls on second mirror and is reflected from there parallel to first mirror. The value of $\theta$ is

Two discs are rotating about their axes, normal to the discs and passing through the centres of the discs. Disc D1 has 2 kg mass and 0.2 m radius and initial angular velocity of 50 rad s${}^{-1}$. Disc D2 has 4 kg mass, 0.1 m radius and initial angular velocity of 200 rad s${}^{-1}$. The two discs are brought in contact face to face, with their axes of rotation coincident. The final angular velocity (in rad s${}^{-1}$) of the system is

The ratio of radii of gyration of a circular ring and a circular disc, of the same mass and radius, about an axis passing through their centres and perpendicular to their planes are

A small object of uniform density rolls up a curved surface with an initial velocity 'v'. It reaches upto a maximum height of $\frac{3v^{2}}{4g}$ with respect to the initial position. The object is

A rod PQ of mass M and length L is hinged at end P. The rod is kept horizontal by a massless string tied to point Q as shown in figure. When string is cut, the initial angular acceleration of the rod is

In a n-type semiconductor, which of the following statements is true?

One way in which the operation of a n-p-n transistor differs from that of a p-n-p

In a common emitter (CE) amplifier having a voltage gain G, the transistor used has transconductance 0.03 mho and current gain 25. If the above transistor is replaced with another one with transconductance 0.02 mho and current gain 20, the voltage gain will be

The output from a NAND gate is divided into two in parallel and fed to another NAND gate. The resulting gate is a

The output (X) of the logic circuit shown in figure will be

In an unbiased p-n junction, holes diffuse from the p-region to n-region because of

The wettability of a surface by a liquid depends primarily on

In the given (V $-$ T) diagram, what is the relation between pressure P1 and P2?

The amount of heat energy required to raise the temperature of 1 g of Helium at NTP, from T1K to T2K is

Two Carnot engines A and B are operated in series. The engine A receives heat from the source at temperature T1 and rejects the heat to the sink at temperature T. The second engine B receives the heat at temperature T and rejects to its sink at temperature T2. For what values of T the efficiencies of the two engines are equal

A system is taken from state a to state c by two paths adc and abc as shown in the figure. The internal energy at a is $U_a = 10\text{ J}$. Along the path adc the amount of heat absorbed dQ1 $=$ 50 J and the work obtained dW1 $=$ 20 J whereas along the path abc the heat absorbed dQ2 = 36 J. The amount of work along the path abc is

A gas is taken through the cycle

A $\rightarrow$ B $\rightarrow$ C $\rightarrow$ A, as shown. What is the net work done by the gas?

Which of the following relations does not give the equation of an adiabatic process, where terms have their usual meaning?

During an adiabatic process, the pressure of a gas is found to be proportional to the cube of its temperature. The ratio of $\frac{C_p}{C_v}$ for the gas is

If an experiment four quantities a, b, c and d are measured with percentage error 1%, 2%, 3% and 4% respectively.

Quantity P is calculated as follows P $= \frac{a^3b^2}{cd}$ % error in P is

The pair of quantities having same dimensions is

A source of unknown frequency gives 4 beats/s when sounded with a source of known frequency 250 Hz. The second harmonic of the source of unknown frequency gives five beats per second, when sounded with a source of frequency 513 Hz. The unknown frequency is

Two sources P and Q produce notes of frequency 660 Hz. each. A listener moves from P to Q with a speed of 1 ms${}^{-1}$. If the speed of sound is 330 m/s, then the number of beats heard by the listener per second will be

If we study the vibration of a pipe open at both ends. then the following statement is not true.

A wave travelling in the + ve x-direction having displacement along y-direction as 1 m, wavelength 2$\pi$ m and frequency of $\frac{1}{\pi}$ Hz is represented by

The length of the wire between two ends of a sonometer is 100 cm. What should be the positions of two bridges below the wire so that the three segments of the wire have their fundamental frequencies in the ratio 1: 3: 5.

A parallel beam of light of wavelength $\lambda$ is incident normally on a narrow slit. A diffraction pattern is formed on a screen placed perpendicular to the direction of the incident beam. At the second minimum of the diffraction pattern, the phase difference between the rays coming from the two edges of slit is

The reddish appearance of the sun at sunrise and sunset is due to

In Young's double slit experiment, the slits are 2 mm apart and are illuminated by photons of two $\circ \quad \circ$

wavelengths $\lambda_1$ = 12000 $\text{\AA}$ and $\lambda_2$ = 10000 $\text{\AA}$. At what minimum distance from the common central bright fringe on the screen 2 m from the slit will a bright fringe from one interference pattern coincide with a bright fringe from the other?

In Young's double slit experiment the distance between the slits and the screen is doubled. The separation between the slits is reduced to half. As a result the fringe width

A particle with total energy E is moving in a potential energy region U(x). Motion of the particle is restricted to the region when

One coolie takes 1 minute to raise a suitcase through a height of 2 m but the second coolie takes 30 s to raise the same suitcase to the same height. The powers of two coolies are in the ratio

A uniform force of $\left(3\hat{i} + \hat{j}\right)$ newton acts on a particle of mass 2 kg. Hence the particle is displaced from position $\left(2\hat{i} + \hat{k}\right)$ metre to position $\left(4\hat{i} + 3\hat{j} - \hat{k}\right)$ metre. The work done by the force on the particle is