Physics Questions

are arra 32 The conducting shells A and B are shown below If charge on the shell B is q then electric flux linked with the spherical gaussian surface S is 1 619 Q 2 200 G

Minimum resonating length of a closed organ pipe is 50 cm when it is vibrated by same frequency then next resonating length will be 1 250 cm 2 200 cm 260 3 150 cm 4 100 cm d frequency is 50 Hz then nath difference will be at the phase differenc

5 At the centre of a fixed large circular coil of radius R a much smaller circular coil of radius r is placed The two coils are concentric and are in the same plane The larger coil carries a current I The smaller coil is set to rotate with a constant angular velocity about an axis along their common diameter Calculate the emf induced in the smaller coil after a time t of its start of rotation a c Mol wr sin oot 4R Mol sin oot 2R b d Mol AR MO 2 R 00 sin cot 002 sin oot

A train moving towards a tunnel in a huge mountain with a speed of 12 m s sounds its whistle If the driver hears 6 beats per second speed of sound in air is 332 m s the frequency of the whistle is 1 80 Hz 2 120 Hz 3 160 Hz 4 240 Hz

Necessary condicition for interference is that 1 The amplitudes of two waves may differ but the phase difference is constant 2 The amplitudes of two waves are same and the phase difference is constant 3 The amplitudes of two waves are same and the phase difference may change 4 The amplitudes of two waves may differ and the phase difference may vary

When a bicycle is in motion and pedalled the force of friction is exerted by ground on two wheels is such that it acts In backward direction on rear wheel and forward direction of front wheel Backward direction on both wheels Forward direction on both wheels In forward direction on rear wheel and backward direction on front wheel

Four charge of 1 C 1 C 1 C and 1 C are placed at the vertices of a square of side 2 cm in sequence Net force experienced by 0 1 C charge at the centre of square 1 9 N 2 18 N 3 36 N 4 Zero

In a transverse progressive wave of amplitude A the maximum particle velocity is four times its wave velocity The wavelength of the wave is 4AW BU K k 1 Aw L LIAU TA 4 AW W 4A 23 1 k 4 2 A TA 3 RA

The property of a medium necessary for wave propagation is 1 Its inertia 2 Its elasticity Water wave are 3 Its low resistance Exegy waste il TO 4 All of above resistance move

1 f In case of a forced vibration the resonance wave becomes very sharp when the 1 applied periodic force is small 2 quality factor is small 3 damping force is small 4 restoring force is small both transvere S and longitudinal P sound waves in the ea

An interference is observed due to two coherent sources A B separated by a distance 42 along the y axis where is the wavelength of the source A detector D is moved on the positive x axis The number of points on the x axis excluding the points x 0 x at which maximum will be observed is A B D 4 infinite 37 277

A graph is drawn between force acting and time for which it acts on particle The area under the curve between time interval t and to giv Momentum of particle Force acting on particle Change in momentum of particle Acceleration of the particle

32 7 A wave y 10 sin ax bt is reflected from a dence medium at an origin If 81 of energy is reflected then the equation of reflected wave is 1 y 8 1 sin ax bt y 9 sin ax bt 2 y 8 1 sin ax bt 4 y 10 sin ax bt

Q7 Two points A and B are on a disk that rotates about an axis Point A is three times as far from the axis as point B If the speed of point B is v then what is the speed of point A a v b 9v c v 3 d 3v e 3 v

1 2 2 4 3 5 In periodic table if elements n 5 does not exits then total number of elements will be L 50 2 60 3 110 4 182 According to Bohr s model of hydrogen atom relation between principal quantum number n and

A car of mass 900 kg negotiates a banked curve of radius 90 m on a frictionless road If the banking angle is 45 the optimum speed of the car is g 10 m s 5 m s 10 m s 15 m s 30 m s 7

Two metallic sphere rland r2 are touched and separated f ind the ratio of their self energy For this how are they ge tting U kq 2 2r by 2r shouldn t it just be by r aka ii iii Q iv Q V V V 2 r 165 U Q 4 Disions of Aakash ucatio 2 E KQ 2r KQ2 2 1 KQ 12 JEE

A conducting body has a cavity in it as shown in the diagram below A point charge is held at the centre of the cavity The electric flux linked with the closed surface S shown dotted is 1 a CO q S 2 200

Q 2 Two resistors are connected in series gives an equivalent resistance of 100 When connected in parallel gives 2 4 2 Then the individual resistance are a Each of 5 Q b 6 2 and 4 Q c 702 and 4 Q d 8 Q and 2 Q

If in an excited state of hydrogen atom n 5 then value of n I m s will l be 1 5 4 4 12 2 f hydrogen atom 1 2 7 7 5 4 8 7 5 2 2 is 1 7 x 10 27 kg and inter atomic distance is 4 x 10 10 m Then mor 3 6 6 5 ARKINGA 1

A point charge q is kept at the centre of the circle formed by cutting a spherical shell by a plane as shown The electric flux linked with the remaining surface of the shell is then 1 p 3 Q 200 5 Q 2 g 200 a

Asseertion Water waves in a river are not polarized Reason Water waves are longitudinal as well as transverse in nature 1 If both Assertion Reason are true the Reason is a correct explanation of the Assertion 2 If both Assertion and Reason are true but Reason is not a correct explanation of the Assertion 3 If Assertion is true but the Reason is false 4 If Assertion Reason both are false lected waves is inverted A

25m 46 Monochromatic radiation emitted when electron on hydrogen atom jumps from first excited to the ground state 51 irradiates a photosensitive material The stopping potential is measured to be 3 57 V The threshold frequency of the AIPMT Pre 2012 materials is 1 4 x 10 5 Hz 2 5 x 10 5 Hz 63 1 6 x 1015 Hz 4 2 5 x 10 5 Hz liug 083 cm in the presence of a magnetic field of 0 25 Wb m The

3 v V 1 L L 2 n A whistle revolves in a circle with angular speed 20 rad sec using a string of length 50 cm If the frequency c sound from the whistle is 385 Hz then what is the minimum frequency head by an observer which is far away fre 340m s the centre velocity of sound V sound 1 385 Hz 2 374 Hz 3 394 Hz 4 333 Hz

1 i ii and iii When a stretched wire and a tuning fork are sounded together 5 beats per second are produced when length of wire is 95 cm or 100 cm frequency of the fork is AILMS 2017 1 90 Hz 2 100 Hz 4 195 Hz Asseertion Water waves in a river are not polarized 3 105 Hz AIMS 2018 1 1 5

radiation of photon energy 1 Two 12 Three Accrding to Bohr s 3 Four 4 One AD When photons of energy hv fal on an aluminium plate of work function E photoelectrons of maximum kinetic energy K are ejected If the frequency of the radiation is doubled the maximum kinetic energy of the ejected photo electrons will be AIPMT 2006 1 K E 2 2K voton of energy 3 K Me Y is kg m s will be 4 K hv AIPMT 2006

919 A copper wire is wound on a wooden frame whose shape is that of an equilateral triangle If the linear dimension a factor of 3 of each side of the frame is increased by keeping the number of turns of the coil per unit length of the frame the same then the self inductance of the coil a increases by a factor of 27 b decreases by a factor of c increases by a factor of 3 d decreases by a factor of 9

6 A cube of side a has a charge q at each of its vertices The net electric field intensity at its centre is r is the distance between a corner and the centre and k 1 Zero 1 ARE 12qX 3 k 12q 2 2 K 2 20 4 k6q

A current of 10A is flowing east 1 poin to west in a long wire kept horizontally in the east west direction Find the magnetic field in the vertical plane at a distance 50cm upwards O 4x 10 5 T 2x 10 5 T O 2x 10 6 T O 4x 10 6 T

A balloon with mass 20 kg is moving downward with an acceleration 2 2 m s2 What mass Am of its contents be removed so that it starts moving up with same acceleration g 9 8 m 2 66 kg 7 33 kg 4 66 kg 5 33 kg

Four charges of1 c 2 C 3 C and 6 C are placed one at each corner of the square of side 1m The square lies in the x y plane with its centre at the origin O The electric potential is non zero at Origin O The electric potential is zero everywhere along the x axis only if the sides of the sqaure areparallel to x and y axis The electric potential is zero everywhere along the z axis for any orientation of the square in the x y plane The electric potential is not zero along the z axis except at the origin

1 15 You are travelling in a car during a thunder storm in order to protect yourself from lightening would you prefer to 1 Remain in the car 2 Take shelter under a tree 3 Get out and be flat on the ground 4 Touch the nearest electrical pole

TV1 2 An electron of mass m with an initial velocity v viv 0 enters an electric field E Ei E constant 0 at t 0 If is its de Broglie wavelength initially then its de Broglie wavelength at time t is NEET 2018 4 2 Ap 1 E my 2 A 1 1 mv 3 At hit of the hydrogen atom is NEET 2018

In the Davisson and Germer experiment the velocity of electrons emitted from the electron gun can be by AIPMT 2011 increasing the potential difference between the anode and filament 2 increasing the filament current 3 decreasing the filament current 1 decreasing the potential difference between the anode and filament JAIPMT 2011

Relation between wavelength of photon and electron of same energy is 1 ph G 2 ph c 4 3 ph then value of n I m s will be ph constan

A B Consider two very long straight insulated wires oriented at right angles The wires carry currents of equal magnitude in the directions shown in the figure above What is the net magnetic field at point P Hol 2ra x 9 Hol 2 Ho C 2 D Hol na a x y z a La

mc h The photoelectric threshold wavelength of silver is 3250 x 10 10 m The velocity of the electron ejected from a silver surface by ultraviolet light of wavelength 2536 x 10 10 m is Given h 4 14 x 10 5 eV s and c 3 x 10 ms 1 0 6 10 ms NEET 2017 MI 2 61 10 ms 3 0 3 10 ms 4 6 10 ms Proglic wavelength of a neutron in thermal equilibrium with heavy water at a temperature T kelvin and mas INEET 2017

The velocity time graph of a body travelling along a straight line is given below The distance travelled and displacement of the body are respectively Vimai A 6m 0 m B 6m 3m DLO

The wavelength involved in the spectrum of deuterium D are slightly different from that of hydrogen spectrum because 1 size of the two nuclei are different 2 nuclear forces are different in the two cases 3 masses of the two nuclei are different 4 attraction between the electron and the nucleus is different in the two cases 17 the energy required to remove the electron from the

D H 2V 2 3V 3 5V An electron in the hydrogen atom jumps from excited state n to the ground state The wavelength so emitted illumi nates a photosensitive material having work function 2 75 eV If the stopping potential of the photoelectron is 10 V the value of n is AIPMT 2011 4 3 2 4 3 5 4 2 for a photon to be emitted by hydrogen atom according t 2011

Light of wavelength 500 nm is incident on a metal with work function 2 28 eV The de Broglie wavelength of t emitted electron is NEET 201 1 2 8 x 109 m 2 2 8 x 10 12 m 3 2 8 x 10 10 m 4 2 8 x 109 m

In the phenomenon of electric discharge through gases at low pressure the colored glow in the tube appears as a result of AIPMT 2008 1 excitation of electrons in the atoms 2 collision between the atoms of the gas 3 collisions between the charged particles emitted from the cathode and the atoms of the gas 4 collision between different electrons of the atoms of the gas

1 0 6 10 ms 2 61x10 ms 3 0 3x10 ms The de Broglie wavelength of a neutron in thermal equilibrium with heavy water at a temperature T kelvin and mass m is NEET 2017 h 43 3mkT 2h 2 3mkT 3 2h mkT h 4 mkT is incident on a metal plate the maximum velocity

When a metallic surface is illuminated with radiation of wavelength the stopping potential is V If the same surface is illuminated with radiation of wavelength 22 the stopping potential is V 4 The threshold wavelength for the metallic surface is NEET 2016 1 A 2 32 3 42 4 52 F The ratio of de Broglie wavelengths associated with

neutron 2 deutron 3 alpha 4 tritium The threshold frequency for a photosensitive metal is 7 x 1013 Hz If light of frequency 10 4 Hz is incident on metal then maximum kinetic energy of emitted electron is AIIMS 20 1 4 x 10 20 J 2 8 x 10 20 J 3 2 x 10 20 J ric affect is seen only when electron are bound 4 10 20 J AIIMS 20

A block of mass 1kg is placed over a plank of mass 2kg The length of the plank is 2m Coefficient of friction between the block and the plank is 0 5 and the ground over which plank is placed is smooth A constant force F 30N is applied on the plank is hor izontal direction 1 kg The time after which the block will separate from the plank is g 10 m s2 2m 2 kg 2 m F 30 N WALEKS

11 1 2 A negative charge is placed at some point on the line joining the two Q charges at rest The direction of motics of negative charge will depend upon the position of negative charge alone 2 magnitude of negative charge alone 3 both on the magnitude and position of negative charge 4 magnitude of positive charge no plomb of charge Number of additional electrons on it will be

Modern Phys A photon of wavelength less than threshold wavelength A is incident on a metal surface of work function W The de Broglie wavelength of the ejected electron of mass m is RPMT 2014 h he 1 h 2m E W 2 2m w W he W 0 X h he 2m W 2 hc 4 h 2m Wo

H 30 6 eV 2 13 6 eV 3 13 6 eV 4 In Bohr series of lines of hydrogen spectrum the third line from the red end corresponds to which one of the followi inter orbit jumps of the electron for Bohr orbits is an atom of hydrogen 1 3 2 2 5 2 3 4 1 4 2 5 ll of mass 60 moving with a velocity of 10 metres per second is approxima

For the circuit shown A C Current across AC is 0 98A Current across DB is 2 41A 1 2 602 2 1 C 71002 D 49V 202 B D wy 70 L 1 2 Y Current across CD is 0 34A Current across AD is 2 75A 55