Physics Questions

Hence flux through plane surface 15 An electric dipole moment P is lying along a uniform electric field E The work done in rotating the dipole by 90 is AIPMT Prelims 2006 1 2 pE 4 2 2 0 pE 2 3 2pE ish undations imited volt m also in the

A converging lens of focal length 15 cm and a converging mirror of focal length 20 cm are placed with their principal axes coinciding A point source S is placed on the principal axis at a distance of 12 cm from the lens as shown in figure It is found that the final beam comes out parallel to the principal axis Let the separation between the mirror and the lens be 10 x k Find k AA S 1 M S P 5

A beaker filled with water is at rest in a car that accelerates to the right with an acceleration 5m s A simple pendulum of length 1 5 has a small wooden bob with the wood s specific gravity s 0 8 is fixed to the floor of the beaker as shown in the diagram 1 Find the angle made by the string with the vertical Will the string tilt towards right or towards left

3 h h h 4 h 2h 3h A particle of unit mass undergoes one dimensional motion such that its velocity varies according to v x 3x 2 where and n are constants and x is the position of the particle The acceleration of the particle as a function of x is given by 1 23 x 2n 1 3 2n x 2n 1 2 2n e 4n 1 14 2n x in 1 NEET 2015

A cube of ice floats partly in water and partly in K oil Fig 1 Find the ratio of the volume of ice immersed in water to that in K oil Specific gravity of K oil is 0 8 and that of ice is 0 9 K Oil Water

12 A thin conducting ring of radius R is given a charge Q The electric field at the centre 0 of the ring due to the charge on the part AKB of the ring is E The electric field at the centre due to the charge on the part ACDB of the ring is APMT Prelims 2008 1 3E along OK a A sh 2 SE along 4 E along KO dations

The position x of a particle with respect to time t along x axis is given by x 9t t where x is in metre and t in second What will be the position of this particle when it achieves maximum speed along the x direction AIPMT Scr 2007 3 81 m 2 54 m 1 32 m 4 24 m orticle starting from the origin 0 0 moves in a straight line in the x y plane Its coordinates at a later time are

3d The new value of the 1 2 F 2 F 3 4 7 2F 3 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 perpendicular to its length into three equal parts and three parts are then place on each other with their like poles together The time period of this combination will be AIEEE 2004 1 2s 2 2 3s 3 2 3 s 4 2 3 s HO AIEEE 2004

1 1 m s 27 m s The motion of a particle along a straight line is described by equation x 8 12 t t where x is in metre and t in second The retardation of the particle when its velocity becomes zero is AIPMT Pre 2012 1 24 ms 2 2 zero 3 6 ms 4 12 ms A stone falls freely under gravity It covers distances h h and h in the first 5 seconds the next 5 seconds and the next INEET 2013

07 S 1 S A ball is thrown vertically upwards Which of the following plots represents the distance time graph of the ball during its flight if the air resistance is not ignored AIIMS 2003 11 2 1S 3 s S 1 time graphs shows a realistic situation for a body in motion AIIMS 2004

29 30 A current loop ABCD is held fixed on the plane of the paper as shown in the figure The arcs BC radius b and radius a of the loop are joined by two straight wires AB and CD A steady current I is flowing in the loop An made by AB and CD at the origin O is 30 Another straight thin wire with steady current I flowing out of the plane AIEEE 200 the paper is kept at the origin 3 aA 9 30 The magnitude of the magnetic field due to the loop ABCD at the origin O is l b a MI b a 4 ab 24ab H 2 b a a b 4T 2 B 4 zero Due to the presence of the current I at the origin 1 The forces on AD and BC are zero HI I 2 The magnitude of the net force on the loop is given by 4t II 3 the magnitude of the net force on the loop is given by 24ab 4 the forces on AB and DC are zero a a b 2 b a a b a

A charge particle is moving along electric field as shown in figure What is horizontal displacement of the charge particle when it descends a distance of y Given Q m 9 6 x 10 C kg E 5 x 10 V m y 84 cm g 10 m s 0 403 x 108m 2 4 03 x 10 0m 50 g 3 4 03 10 8m 4 8 06 x 10 m AIIMS 2018 14 03X10 3m Lugh that the magnetic axial line is in

X 11 1 1 4 9 2 1 2 4 3 1 3 5 A point initially at rest moves along x axis Its acceleration varies with time as a 6t 5 m s If it starts from origin the distance covered in 2 s is 1 20 m 2 18m 3 16 m 4 25 m RPMT 2007 from the origin 0 0 moves in a straight line in the x y plane Its coordinates at a later time are

1 2 ms 2 4 ms A rocket is fired vertically from the ground with a resultant vertical acceleration of 10 ms 2 The fuel is finished in 1 mi and it continues to move up What is the minimum height reached 1 42 3 km 2 48 4 km 3 36 4 km 4 25 6 km AIIMS 201

Two pieces of metal when immersed in a liquid have equal upthrust acting on them then a Both pieces must have equal weights b Both pieces must have equal densities c Both pieces must have equal volume d Both are floating to the same depth A fisherman hooks an old log of wood of weight 12 N and volume 1000 cm He pulls the log half way ou

In your laboratory you trace the path of light rays through a glass slab for different values of angle of incidence i and in each case measure the values of the corresponding angle of refraction r and angle of emergence e On the basis of your observations your correct conclusion is a zi is more than Zr but nearly equal to Ze b zi is less than r but nearly equal to Ze e zi is more than Ze but nearly equal to r d Zi is less than Ze but nearly equal to Zr

A current flows in an infinitely long wire with cross section in the form of a semicircular ring of radius R The magnitude of the magnetic induction along its axis is AIEEE 2011 14 1 1 R 2 2 R 3 1 2TR HI 4 R

from the centre is 54 T What will be its va 4 2 150 HT 3 125 HT 5F 250 HT Two long conductors separated by a distance d carry currents I and I in the same direction They exert a force F each other Now the current in one of them is increased to two times and its direction is reversed The distance is al increased to 3d The new value of the force between them is AIEEE 200 1 2 F 2 F 3 73 2F 3 4 F 3 i width and breadth The time period of its oscillation in a vibrat then pla unto

1 6 m 2 4 m 3 A bus is moving with a speed of 10 ms on a straight road A scooterist wishes to overtake the bus in 100 s If the bus is at a diatence of 1 km from the scooterist with what speed should the scooterist chase the bus H 20 ms 2 40 ms 3 25 ms 4 10 ms AIPMT Scr 2009 tiolo ctarts its motion from rest under the action of a constant force If the distance covered in first 10s is s and JAIPMT Scr 2009

A divergent lens has a focal length of 20 cm At what distance should an object of height 4 cm from the optical centre of the lens be placed so that its image is formed 10 cm away from the lens Find the size of the image also

will q 2 5 q 3 3 q A thin circular disk of radius R is uniformly charged with density o 0 per unit area The disk rotates about its axis with a uniform angular speed The magnetic moment of the disk is AIEEE 2011 12 1 TR ow 00 TR 4 4 2 R w rface of non condcting disc of radius R The disc rotates about an axis this rotation 3 JO

cm Assuming it to be uniform the retardation will be 2 10 x 10 m s 4 15 x 10 m s 3 12 x 10 m s 4 14 5 m s A body A starts from rest with an acceleration a After 2 s another body B starts from rest with an acceleration a If AIIMS 2001 they travel equal distances in 5th s after the starts of A the ratio a a will be equal to 1 9 5 2 5 7 3 5 9 4 7 9 dy starting from rest moves along a straight line with a constant acceleration The variation AIIMS 2003 of speed v with

A magnetic needle is kept in a non uniform magnetic field It experiences 1 a torque but not a force 2 neither a force nor a torque 3 a force and a torque 4 a force but not a torque

3 curved path of electron is more curved than that of prot 4 path of proton is more curved 2 com If a current is passed through a spring then the spring will 1 expand Land carrying currents i and i respectively are inclined at an angle 9 to each other What is the force on a small in figure due to the magnetic field of wire 1 AIEEE 2002 3 remain same compress 4 none of these AIEEE 2002

The resistance between the terminal points A and B of the given infinitely long circuit will be B 3 1 1 3 1 3 2 3 192 www www 192 www 192 ww 192 www 192 102 www 122 www 192 Up to infinity

Preeti reached the metro station and found that the escalator was not working She walked up the stationary escalator in time t On other days if she remains stationary on the moving escalator then the escalator takes her up in time t NEET 2017 The time taken by her to walk up on the moving escalator will be t t 1 1 2 t 1 3 t t 4 1 1 2

1 15 m 2 10 m A particle moves along a straight line OX At a time t in seconds the distance x in metres of the particle from O is given by x 40 12t t How long would the particle travel before coming to rest AIPMT Ser 2006 1 24 m 2 40 m 3 56 m 4 16 m Two bodies A of mass 1kg and B of mass 3kg are dropped from heights of 16 m and 25 m respectively The ratic JAIPMT SCE 2006

A particle moving along x axis has acceleration f at time t given by f f 1 7 where f and T are constants The particle at t 0 has zero velocity In the time interval between t 0 and the instant when f 0 the particle s velocity v is AIPMT Scr 2007 1 f T 2 T 3 f T2 4 6 T and moving with an acceleration 4 3 ms2 in the third second

A man throws balls with the same speed vertically upwards one after the other at an interval of 2 seconds What should be the speed of the throw so that more than two balls are in the sky at any time Given g 9 8 m s AIPMT Scr 2003 1 Any speed less than 19 6 m s 3 more than 19 6 m s 2 Only with speed 19 6 m s 4 At least 9 8 m s

1 expand 2 compress Wires 1 and 2 carrying currents i and i respectively are inclined at an angle 0 to each other What is the force on a small element dl of wire 2 at distance r from wire 1 as shown in figure due to the magnetic field of wire 1 AIEEE 2002 1 i i dl tan 0 Ho 2fr Ho 3 4T i i dl cos 0 1 dl 2 4 Ho 2fr i i dl sin 0 Ho 4fr i i dl sin 0 doflected in a magnetic field The compound can emit E 20021

Two sources of emf 6 V and internal resistance 392 20 are connected to an external resistance R as shown If potential difference across battery A is zero then value of R is 19 222 302 A 6 V 392 B 6 V 222 www R

21 d 2nd Relative permittivity and permeability of a material are e and respectively Which of the following values of these quantities are allowed for a diamagnetic material AIEEE 2008 1 1 5 H 0 5 3 1 5 H 1 5 2 0 5 0 5 4 0 5 H 1 5 height of 4 m from the ground and carries a current of 100 A from east to west 0001

4 31 B Speeds of two identical cars are u are 4u at a specific instant The ratio of the respective distances in which the two cars are stopped in the same time RPMT 2009 1 1 1 2 1 4 3 1 8 4 1 16 man throws balls with the same speed vertically upwards one after the other at an interval of 2 seconds What should Given 98 m s

1 s 2s 2 s 3s 3 s 4s 4 S A ball is dropped from a high rise platform at t 0 starting from rest After 6 seconds another ball is thrown downwards from the same platform with a speed v The two ball meet at t 8s What is the value of v Take g 10 ms 2 AIPMT 2010 1 75 ms 2 55 ms 3 40ms 4 60ms ouer of 20m height drops a stone Assuming g 10 ms2 the velocity with which it hi LARMT Sar 201

the particle moves with a constant acceleration A ball is thrown vertically upwards with a velocity of 30 m s If the acceleration due to gravity 10 m s what will be the distance travelled by it in the last second of motion 1 5 m 2x10 25 m 4 30 m m diffono One hall is dropped 2 sec after the other but they both st

1 I m s 2 5 m s 3 7 m s A particle after starting from rest experiences constant acceleration for 20 sec If it covers a distances in first 10 sec RPMT 2003 then the distance covered during next 10 sec will be 1 s 4 4s 2 2s 3 3s uch of mass mare dropped from height h and 2h respectively then the ratio of their times to FRRMIT 2003

4 the magnetic field at all points inside the pipe is the same but not zero A charged particle with charge q enters a region of constant uniform and mutually orthogonal fields and B with a velocity v perpendicular to both and B and comes out without any change in magnitude or direction AIEEE 2007 of V Then v ExB B 4 V BxE E 3 v ExB E 2 v x B through a magnetic field perpendicular to its direction Then AIEEE 2007

Figure shows the position of a particle moving on the x axis as a function of time 10 w 6 1 the particle has come to rest 6 times 2 the maximum speed is at t 6 sec 3 the velocity remains positive for t 0 to t 6 sec 4 the average velocity for the total period show in negative gors A and B t sec

3ft 3T A deflection magetometer is adjusted in the usual way When a magnet is introduced the deflection observed is 8 and the period of oscillation of the needle in the magnetometer is T When the magnet is removed the period of oscillation is To The relation between T and To is AIIMS 2017 T T cos 0 2 T T cos 0 To cose 3 T 4 T T3 cose

1 7 8 m 2 78 m 3 15 6 m Two bodies are thrown vertically upward with the same initial velocity of 98 m s but 4 sec apart Hong after the first one is thrown when they meet 1 10 sec 2 11 sec 3 12 sec 4 13 sec

A rectangular coil of length 0 12m and width 0 1m having 50 turns of wire is suspended vertically in a uniform magnetic field of stength 0 2 Weber m The coil carries a current of 2A If the plane of the coil is inclined at an angl of 30 with the direction of the field the torque required to keep the coil in stable equilibrium will be NEET 2015 1 0 24 Nm 3 0 15 Nm 4 0 20 Nm 12 0 12 Nm

Mark the correct statement 1 A solid conducting sphere holds more charge than a hollow conducting sphere of the same radius 2 Two equipotential surfaces may intersect 3 When a conductor is earthed charge always flows from conductor to earth 4 No work is done in taking a positive charge from one point to another point inside a oborand metallic sphere

The following figures show some velocity V versus time t curves But only some of these can be realised in practice These are hhh n In ii iv 2 only i ii iii i Only i ii and iv iii 3 only ii and iii 4 all of them the figure The maximum

A man standing on the edge of a cliff throws a stone straight up with initial speed u and then throws anothe stone straight down with same initial speed u from the same position Find the ratio of speeds the stone would have attained when they hit the ground at the base of the cliff 1 2 1 2 1 2 3 1 1 4 3 1 The height of the bridge is

1 56 km hour 20 km hour 50 km hour 4 48 km hour A particle moves along a circle with a uniform speed v After it has made an angle of 60 the change in its speed and velocity will be 60 1 v 2 v 0 3 v 3 v 0 LERATION 2 A Buda 560 x

A 500W Carnot engine operates between constant temperature reservoirs at 100 C and 60 0 C What is the rate at which energy is a taken in by the engine as heat and b exhausted by the engine as heat

A ball is thrown upwards it takes 4 s 1 30 ms 2 10 ms 1 3 40 ms 4 20 ms If relation between distance and time is s a bt ct and initial velocity and acceleration Ub 2 ct 2 c 2 b 2 c 3 2 c b 4 b 2 c 2 c RPMT 2 A body falls from a height h 200 m The ratio of distance travelled in each 2 s during t 0 to t 6 s of the jo

Four charges q q q and q are placed at the corner of square of side a as shown in the figure The net electric potential at the centre 1 4 TEO of the square will be k q a a a q a

4 9 1 J 1 4 55 J 1 15 J 2 2 3 J A bar magnet is hung by a thin cotton thread in a uniform horizontal magnetic field and is in equilibrium state The energy required to rotate it by 60 is W Now the torque required to keep the magnet in this new position is

2R A proton carrying 1 MeV kinetic energy is moving in a circular path of radius R in uniform magnetic field What should be the energy of an a particle to describe a circle of same radius in the same field 1 2 MeV 2 1 MeV 0 5 MeV 4 4 MeV AIPMT 2012 Mains magnetic field requires J of work to turn it through 60 The torque