Physics Questions

The linear charge density of the semicircular ring on both side is same in magnitude The electric field intensity at centre O is along T 1 F 3 j AY 2 i 4 1 X Dh 011 4762

A very long hollow metallic pipe is held vertical A small bar magnet with its N pole pointing downwards is allowed to fall through it After a lapse of some time he magnet will be observed to be falling with an acceleration a where a g 2 a g 3 a g 4 a 0

A stone is dropped from the top of a tower and it strikes with 3 km hr against the ground Another stone is thrown vertically downwards from the same top of the tower with a velocity 4 km hr Its velocity wher it strikes the ground will be 1 7 0 km hr 2 5 0 km hr 3 3 5 km hr 4 4 0 km hr the top of a tower with a velocity of 10 m sec If the ball fal

R d At a point A on the earth s surface the angle of dip 8 25 At a point B on the earth s surface the angle of dip 8 25 We can interpret that NEET 2019 1 A and B are both located in the southern hemisphere 2 A and B are both located in the northern hemisphere 3 A is located in the sourthern hemisphere and B is located in the northern hemisphere 4 A is located in the northern hemisphere and B is located in the southern hemisphere NEET 2019 and particles with same momenta enters perpendicular to a constant magnetic field B The

The initial velocity of a particle is 10 m sec and its retardation is 2 m sec The distance covered in the fifth second of the motion will be 1 Ym 2 19 m 3 50 m 4 75 m An obiect is released from some height Exactly after one second another object is released from the sam

Three charges and q are placed at 2 the corner of an equilateral triangle of side a as shown in the figure The net electric dipole moment of the system will be 9 q 2 a a a q 2

A rocket is projected vertically upwards and its time velocity graph is shown in the figure The maximum height attained by the rocket is dea culoration after 20 sece 1000 2 10 km M sec J 20 sec 120 3 100 km are of this graph 60 60 km 10006 Z 3 6 5

3 directed along PO 4 directed perpendicular to the plane of paper A current carrying loop in the form of a right angle isosceles triangle ABC is placed in a uniform magnetic field acting along AB If the magnetic force on the arm BC is F the force on the arm AC is AIPMT 2011 1 2 F 2 F B 3 F C 4 2 F

A truck travelling due to North at 20 m s turns East and travels at the same speed The change in its velocity 1 20 2 m s North East 3 2012 m s South East 3 40 2 m s North East 4 20 2 m s North West 40 Jum hour and the ser

An ideal inductor is in turn put across 220 V 50 Hz and 220 V 100 Hz supply The current flowing through it in two cases will be More in first case More in second case Equal in both cases Zero in first and infinite in second

1 0 24 Nm 12 0 12 Nm 3 0 15 Nm 4 0 20 Nm A proton and an alpha particle both enter a region of uniform magnetic field B moving at right angles to the field B IE the radius of circular orbits for both the particles is equal and the kinetic energy acquired by proton is 1 MeV the energy acquired by the alpha particle will be NEET 2015 2 L MeV 1 1 5 MeV The magnetic susceptibility is negative for 3 4 MeV 740 5 MeV NEET 2016

1 2R R 2 R 2R 3 R 2R The magnetic needle of a tangent galvanometer is deflected by an angle 30 due to a magnet The horizontal componen of earth s magnetic field is 0 34 x 10 T along the plane of the coil The intensity of magnetic field of magnet is 1 1 96 x 10 T 2 1 96 x 10 5 T 4 1 96 x 105 T 3 1 96 x 10 T RPMT 2009 length of a long solenoid If 4A currents is flowing in the solenoid t

4 The iduced electric field due to the changing magnetic field A metallic rod of mass per unit length 0 5kg m is lying horizontally on a smooth inclined plane which makes an angle of 30 with the horizontal The rod is not allowed to slide down by flowing a current through it when a magnetic field 4 11 32 A of induction 0 25T is acting on it in the vertical direction The current flowing in the rod to keep it stationary is NEET 2018 1 7 14 A NEET 2018 itivity of a moving coil galvanometer is 5div mA and its voltage sensitivity angular deflection per unit 2 5 98 A 3 14 76 A

A bar magnet of length I and magnetic dipole moment M is bent in the form of an arc as shown in figure The new magnetic dipole moment will be INEET 2013 3 1 M 2 NE M C 4 M

1 40 92 2 25 2 A cylindrical conductor of radius R is carrying a constant current The plot of the magnitude of the magnetic field B with the distance d from the centre of the conductor is correctly represented by the figure NEET 2019 1 B R d 2 B R d 3 B R d B 4 Rd the earth s surface the angle of dip

For protecting a sensitive equipment from the extrnal magnetic field it should be 1 placed inside an aluminium can 2 placed inside an iron can 3 wrapped with insulation around it when passing current thought it 4 surrounded with fine copper sheet filed is produced

A rectangular loop of length 20 cm along y axis and breadth 10 cm along z axis carries a current of 12 A If a un magnetic field 0 3 0 43 acts on the loop the torque acting on it is 1 9 6 x 10 Nm along x axis 3 9 6 x 10 2 Nm along z axis 2 9 6 x 10 Nm along y axis 4 9 6 x 10 Nm along z axis

Four wires of equal length are bent in the form of four loops P Q R and S These are suspended in a uniform magnetic field and same current is passed in them The maximum torque will act on

A closed loop PQRS carrying a current is placed in a uniform magnetic SR and RQ are F F and F respectively and are in the plane of the paper and along the directions shown the AIPMT 2008 directions shown the force on the segment QP is F S 1 R E

3 3 F A current loop consists of two identical semicircular parts each of radius R one lying in the x y plane and the other in x z plane If the current in the loop is i The resultant magnetic field due to the two semicircular parts at their common centre is AIPMT MAINS 2010 1 Hoi 2 2R 2 Hi 2R 3 4R 4 2R

There are 50 turns of a wire in every cm length of a long solenoid If 4A currents is flowing in the solenoid the approximate value of magnetic field along its axis at an internal point and at one end will be respectively 1 12 6 x 10 Wb m 6 3 x 10 Wb m 2 12 6x 10 3 Wb m 25 1 x 10 Wb m 4 25 1 x 10 Wb m 12 6 x 105 Wb m 3 25 1 x 10 3 Wb m 12 6 x 10 Wb m RPMT 2009

A body covered a distance of L m along a curved path of a quarter circle The ratio of distance to displacement is 2 2 2 T if he starts from one end of the track and 2 2 2 T T 3 dien 4

6 Points A block with a mass of 4 00 kg connected to a spring is undergoing simple harmonic motion The block has a maximum velocity of 4 50 m s Some time later the block has compressed the spring by 10 0 cm coming to a complete stop What is the period of oscillations 0 3185 0 115

1 infinite 2 zero 4 non uniform The correct curve between the magnetic induction 2 along the axis of a along solenoid due to current flow i in it and distance x from one end is B4 nk In 2 4 BA B B4 BA 25 amp The magnetic field at its centre is

One mole of oxygen is taken from 1 to 2 by process shown in diagram What heat is rejected out of gas P Pa 600 150 0 ww 0 2 225 J 105 J 335 J 450 J 1 0 8 V m

A long straight metal rod has a radius of 2 0 mm and a surface charge of density 6 nC m Determine the magnitude of the electric field 6 mm from the axis O A 226 N C O B 452 N C C ON C D 71 97 N C E 113 N C

5 The vector form of Biot Savart s law for a current carrying element is 3 dB Ha Id xf 4 r dB Ho 4 Idl sin p r 2 dB H Id xf 4 T RPMT 2009 4 dB H Id7 xi 4 r mathe Y axis enters a region where a magnetic fie

Soft iron is used in many electrical machines for 1 low hysteresis loss and low permeability 3 high hysteresis loss and low permeability For protecting a sensitive equipment from the extrnal magnetic field it should be 2 low hysteresis loss and high permeability 4 high hysteresis loss and high permeability

Starting with the equation of motion of a three dimensional isotropic harmonic oscillator i 1 2 3 dp dt deduce the conservation equation where kr dA dt A 0 1 2 1 P P kr r 3 2m Note that we will use the notations T T2 T3 and x y z interchangeably and similarly

A particle of charge q and mass m move in a circular orbit of radius r with frequency v The ratio of th magnetic moment to angular momentum is RPMT 2014 2q m 2 q 2m 3 9 2mr 9 2m The unife

portion of diameter R is cut out from a uniform circular disc of mass M and radius R as shown in figure The moment of inertia of the remaining shaded portion of the disc about an axis passing through the centre O of the disc and perpendicular to its plane is RR 15m Cut out portion 1 MB 13 3 MR 4 MR

A conducting rod of length East West falls vertically under gravity in a region of uniform magnetic field B North South horizon The magnetic field vecto Bis inclined at angle 0 with vertical as shown in figure At any instant rod is falling with velocity v the emf induced in rod is B B V Bv sine Zero BycosA

A student focuses the image of a candle flame placed at about 2 m from a convex lens of focal length 10 cm on a screen After that he moves gradually the flame towards the lens and each time focuses its image on the screen A B C In which direction does he move the lens to focus the flame on the screen What happens to the size of the image of the flame formed on the screen What difference is seen in the intensity brightness of the image of the flame on the screen D What is seen on the screen when the flame is very close at about 5 cm to the lens

A rocket having fuel as its bulk is initially at rest Neglecting effect of gravity when fuel is burning at a constant rate acceleration a of rocket with respect to time is best represented by one of the graphs given below hr min t

In this diagram the angle of incidence the angle of emergence and the angle of deviation respectively have been represented by A y p z B C D x q z P y z p z y

An electric dipole of moment p placed in uniform electric field has minimum potential energy The work done by external agent to rotate this dipole very slowly upto which it has maximum potential energy PE 2PE PE 2

PROPERTIES OF MA When a small magnetising field H is applied to a magnetic material the intensity of magnetisation is proportional 1 H 2 H 2 3 H 4 H How does the magnetic susceptibility X of a paramagnetic material change with absolute temperatue T 1 T

You are given a number of 14 2 resistors each capable of dissipating only 1 7 W without being destroyed What is the minimum number of such resistors that you need to combine in series or in parallel to make a 14 2 resistance that is capable of dissipating at least 14 0 W Number Units

Two insulated wires of infinite length are lying mutually at right angles to each other as shown in Currents 2A and 1 5A respectively are flowing in them The value of magnetic induction at point P will be 10 3 N A m 2 2 x 105 N A m 3cm 4cm P 9 1 5 x105 tesla 4 2 x 10 N A m

Two particles having charges in the ratio 1 2 are projected in a uniform magnetic field with same momentum If they are projected normally to magnetic field then the ratio of radii of their circular paths will be 1 2 3 w

The top of the lake is frozen The air in contact with surface of lake is 20 C Then the maximum temperature of water in contact with lower surface ice will be 6 C 10 0 C C 273 C English

A toy top of constant density do is constructed from a portion of a solid hemisphere of radius R with conical base of the height H The center of the spherical part is at the point where the top spins and the height of the conical base is equal to its radius r Find the moment of inertia of the top about its axis of symmetry HINT Take z axis for the axis of symmetry axis of rotation

The magnetic moment of a circular coil carrying current is 1 directly proportional to the length of the wire in the coil 2 inversely proportional to the length of the wire in the coil directly proportional to the square of the length of the wire in the coil 4 inversely proportional to the square of the length of the wire in the coil

is A straight wire of diameter 0 5 mm carrying a current of 1A is replaced by another wire of diameter 1 mm carrying the same current The strength of magnetic field far away 1 twice the earlier value 3 one quarter of the earlier value 2 one half of the earlier value 4 same as earlier value distance of 5m between them If P and Q carry current of

charge mass An electron is travelling in east direction and a magnetic field is applied in upward direction then electron wi deflect towards 1 south north 3 west 4 east the magnetic field The path followed by the proto

Gas phase sulfur S and gas phase oxygen O have the same molar mass At the same temperature they also have the same A C v B average KE per mole C average rotation KE per mole D average translational KE per mole

a and b 3 a b and c 4 The distance between the plates of a parallel plate condenser is 4 mm and potential difference between them is 200V The condenser is placed in a magnetic field B An electron is projected vertically upwards parallel to the plates with a velocity of 10 m s The electron passes undeviated through the space between the plates The magnitude and direction of magnetic field B will be di H e iu

statement 9 d figure mark the correct Solid neutral conductor R 1 Potential of the conductor is q 4neod 2 Potential of the conductor is q 4neo d R 3 Potential at point B due to the induced qR charges is 4neod d R

A wire loop PQRSP is constructed by joining two semi circular coils of radii r and r respectively as shown in the fig Current i is flowing in the loop The magnetic induction at point O will be MH 2 Hoi 1 4 S R 3 2 1 4 H

A student very cautiously traces the path of a ray through a glass slab for different values of the angle of incidence Zi He then measures the corresponding values of the angle of refraction r and the angle of emergence e for every value of the angle of incidence On analysing these measurements of angles his conclusion would be A Zi Zr Ze B Zi Ze Zr C Zi r Ze D Zi Ze r