Physics Questions

P From an inclined plane two particles P Q are projected with same speed at same angle one up and other down the plane as shown in figure Which of the following statement s is are correct P 0 0 0 A The particles will collide the plane with same speed B The times of flight of each particle are same C Both particles strike the plane perpendicularly D The particles will collide in mid air if projected simultaneously and time of flight of each particle is less than t

a circular path with constant speed then the angle between the direction of accelera and its position vector w r t centre of circle will be 1 Zero 3 T kash Educational 2 TC IN 5 2 4 2

48 A particle of charge q and mass m starts moving from the origin under the action of an electric field E E and B B with a velocity v vj The speed of the particle will become 2v after a time qE Find the value of n

5 When a thin transparent plate of thickness t and refractive index u is placed in the path of one of two interfering beam of light then path between two waves at the position central is 1 1 t 1 3 2 1 t 4 ut to mee Teleg ma

A block of mass m compresses a spring of spring constant k through a distance 17 123 as shown in figure The block is not fixed to the spring The period of motion n Find n m of the block is k m 6247 ci Yc ych An Audig k yg ami a hea 21 ych fa chi Bada Tuch of Mi Elastic Wall Rear 1 2 Aa A zefy HJwz 2 na 38 13 1 k moooo m k n In

1 u 1 5 3 R 10 cm What is focal length of this curved surface Question Type Single Correct Type 1 2 3 4 10 cm 5 cm 20 cm 30 cm

The work function of a photosensitive material 4 0 eV The longest wavelength of light that ca cause photon emission from the substance approximately NEET 2019 Odish 1 310 nm 3 966 nm 2 3100 nm 4 31 nm

Choose the correct statements Whole mass of system is assumed to be concentrated at COM for calculation of moment of inertia O Whole mass of system is assumed to be concentrated at COM for calculation of gravitational potential energ O Whole mass of system is assumed to be concentrated at COM for calculation of linear momentum Whole mass of system is assumed to be concentrated at COM for calculation of kinetic energy

Whole mass of system is assumed to be concentrated at COM for calculation of moment of inertia Whole mass of system is assumed to be concentrated at COM for calculation of gravitational potential energy Whole mass of system is assumed to be concentrated at COM for calculation of linear momentum Whole mass of system is assumed to be concentrated at COM for calculation of kinetic energy

SolveLancer Test 3 moles of hydrogen gas undergoes a cyclic process Assuming the gas to be ideal the heat supplied to the gas is SolveLancer Test a 20510 J b 14510 J c 13510 J d 15530 I 4 atm 2 atm P A D 400 K B C 500 K T

The number of waves in a glass plate of thickness 4 cm is same as in 5 cm of vertical column of water of refractive index 4 3 then refractive index of glass will be Question Type Single Correct Type 1 2 3 5 3 5 4 16 14

When the light of frequency 2vo where vo is threshold frequency is incident on a metal plate the maximum velocity of electrons emitted is v When the frequency of the incident radiation is increased to 5vo the maximum velocity of electrons emitted from the same plate is v The ratio of v to v is NEET 2018 1 1 2 3 2 1 2 1 4 4 4 1

correct option s will result in 1 marks A truck is moving such that block of 1kg mass remain at rest w r t truck then O Acceleration of truck is less than 5 m s Truck 1kg O p 0 5 Acceleration of truck must be greater than 20 m s If acceleration of truck is 25 m s then normal contact force between truck block is 25N If acceleration of truck is 20 m s then friction force between truck block is 10 N

The three 200 g masses in figure are connected by massless rigid rods to form a triangle What is the triangle s rotational kineti energy in joule if it rotates at 3 rad s about an axis through the center 10cm 60 Axis 40cm 60 40cm

A uniform rod of mass m 7kg and length 1 m is fixed from point A which is at a distance 1 4 from one end as shown in the figure The rod is free to rotate in a vertical plane The rod is released from horizontal position Find the reaction force in N at the hinge when kinetic energy of the rod is maximum 114 A

27 A particle of mass M and charge Q moving with velocity describes a circular path of radius R when subjected to a uniform transverse magnetic field of induction B The work done by the field when the particle completes one full circle is Mv A BQv2rR B R 2xR C zero D BQ2TR

12 Each question is followed by two statements P and Q Mark your answer using the following instructions If LCM of two numbers is 90 then what are the numbers P One of the numbers is 18 Q HCF of the numbers is 3 A Question can be answered by using both the statements together but not by either of the statement alone B the question cannot be answered even by using both the statements together C If the question can be answered by using either of the statements alone D If the question can be answered by using one of the statements alone but not by using the other statement alone

6 The minimum thickness of a soap bubble film 1 33 that results in constructive interference in the reflected light if the film is illuminated with light whose wavelength in free space is 600 nm is 2 225 26 nm 1 112 50 nm 3 400 nm 4 176 5 nm

A particle is thrown upward with speed 10 3 m s It strikes the inclined surface as shown in figure If collision is perfectly inelastic find maximum height of particle from ground g 10 m s 45 3m 10 3 m s

9 The total charge enclosed in an incremental volume of 2x10 9 m located at the origin is nC if electric flux density of its field is found as D e siny e cosy 3 2zk C m Given swer 4

A rod of mass M and length L is suspended by a frictionless hinge at the point O as shown in figure A bullet of mass m moving with velocity v in a horizontal direction strikes the end of the rod and gets embedded in it The angular velocity of the rod just after the collision is O mv m M

4 Two slits are separated by a distance of 1 mm are illuminated with red light of wavelength 6 5 x 10 7 metre The interference fringes are observed on a screen placed 1 metre away from the slits The distance between 3rd dark fringe and fifth bright fringe is equal to 1 0 65 mm 3 323 m 2 1 63 mm 4 468 mm

26 Two particles A and B of masses mA and ma respectively and having the same charge are moving in a plane A uniform magnetic field exists perpendicular to this plane The speeds of the particles are VA and Va respectively and the trajectories are as shown in the figure Then A MAVA MBVB C m m and v V B MAVAMVB D m mg and v VB

dissociate into atoms 4 Average lifetime of a hydrogen atom excited to n 2 state is 10 8 s Find the number of revolutions made by the electron on the average before it jumps to the ground state

The diameter of the objective lens of a telescope is 5 0 m and wavelength of light is 6000A The limit of resolution of this telescope will be 1 3600 1 0 03 2 3 03 3 0 06 4 0 15

An electron of mass m with an initial velocity V voi vo 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 1 3 2 1 20 eEo t mvo 2 A 1 4 t eEo mvo

In the circtuit shown which of the following statement is are CORRECT 1 2 Question Type Single Correct Type 3 V 100 2 sin 377t 4 R 1000 X 1000 AAAAAA VOTROVO X 5001 1 Power factor of the circuit is 2 Reactance of the circuit is equal to resistance of the circuit Circuit is not in a state of resonance X 1000 Average power dissipated in the circuit is 100 W C

0 A light has amplitude A after coming out from polariser Angle between transmission axis o analyser and polariser is 60 Light passing through analyser has amplitude 1 2A 3 3A 2 A

19 An object is placed at 15 cm from a convex ler of focal length 10 cm At what distance from ler another convex mirror of radius 12 cm be place such that final image will coincide with object 1 18cm 3 14cm 2 17cm 4 20cm

A particle moves from point 2m 5m 7m to 4m 7m 11m under action of a force F 21 31 7k N find work done by this force 28 J 38 J O 82 J

A conducting ring is placed in a uniform external magnetic field present in the space within the ring and perpendicular to plane of ring The magnetic field changes at a constant rate due to which a current of magnitude 4 amp flows in the ring The resistance of parts PQR and PSR are 40 and 80 respectively Then 1 2 S 3 X x x x X X X X R X X M x x P X X Question Type Single Correct Type X X O The emf induced in the ring 48 V Potential difference between P R is 24 V Potential difference between P R is 10 V Potential difference between P Ris zero as

X ray are produced in Coolidge tube It consists of a thick glass bulb evacuated to about 10 cm of Hg so that no discharge can pass in it A cathode serves as source of electron is made up of tungsten filament heated by a low voltage current A cylindrical metal shield S surrounds the filament and S kept at negative potential with respect to the filament is focuses the electron emitted form the filament on the target T The target is mounted on the surface of a copper block fixed to the end of a copper rod The rod is fitted with fins for air cooling or cooled by circulating water A potential difference of about 20 000 V is applied across the tube to accelerate the electrons The accelerated electrons strike to the target and produces continuous and characteristic x rays 3 In the Coolidge tube experiment Platinum is used as target material for the emission of k series x ray The K L and M energy level of this element are 7 8 x 10 eV 1 2 x 10 eV and 3 x 10 eV respectively C 3 x 10 m s 1 eV 1 6 10 9 and h 6 23 10 4 J s The wavelength of ka lines will be A 0 188 A B 0 376 C 0 999 A D 0 25A

Which of the following statement s regarding EM waves is are false a The ratio of electric field strength En to magnetic field strength Ho of a plane electromagnetic wave in vacuum has the dimensions of electric resistance and is always equal to one b The average value of electric field in a plane electromagnetic wave is independent of electric energy and has a constant non zero magnitude perpendicular to the direction of wave propagation c The frequency of oscillation of energy contained in a small volume through which an electromag netic wave is passing would be double the frequency of the wave d An electron released from rest in the path of a plane electromagnetic wave will start moving along the direction of wave propagation

A wooden cube density of wood d of side e floats in a liquid of density p with its upper and lower surfaces horizontal If the cube is pushed slightly down and released it performs simple harmonic motion of period T ld 1 2 3 2 4 2 p d g ld pg 2 2 lp dg lp V p d g

99 At what angle a ray of light should incident on face AB so that it retraces it s path after reflection from question vered face AC 1 30 3 60 B 301 H 2 45 4 90

An unpolarized light passes through 2 polarizer If the intensity of the transmitted light is 20 that of 11 The the original light what is the angle between the 5 0 transmission axes of the 2 polarizing sheets resa 1 Cos 0 3 2 Cos 0 4 3 Cos 0 6 4 Cos 0 7 1 3

92 A microscope has an objective of 5 mm focal length and eye piece of 30 mm focal length and the magnification is 250 Then the length of the microscope for normal adjustment will be 1 150 mm 2 50 mm 3 100 mm 4 75 mm 3 A telescope has an obiective Telegram

A space ship is sent to investigate a planet of mass M and radius R While hanging motionless in space at a distance 5R from the centre of the planet the space ship fires an instrument package with speed vo as shown in the figure The package has mass m which is much smaller than the mass of the space ship For what value of angle 8 the package will just graze the surface of the planet B faydal 5 kaft v kat Vo afm sin M sin 5R sin 1 1 Correct Answer 1 M 8GM GR 8GM 5R kera 2 2GM 5 R

The plane face of a Plano convex lens of glass 3 2 having focal length 20 cm is silvered What type of mirror will it become and of what focal length f 1 Convex f 20cm 2 Concave f 20cm 3 Convex f 10cm 4 Concave f 10cm

1 1 3 3 3 2 2 2 3 4 3 1 17 A plano convex lens of refractive index 1 5 and radius of curvature 30cm is silvered at the curved surface Now this lens has been used to form the image of an object At what distance from this lens an object be placed in order to have a real image of the size of the object 1 20 cm 3 60 cm 2 30 cm 4 80 cm

3 2n Vg cose 68 Two particles each of mass m are moving in horizontal circle with same angular speed If both string are of san length then the ratio of tension in string T 1 32 3 2 is m 2 3 4 level circular track with unif 1 3 m The direction of F the re tana dvidt F vir For uniform circular m Note sider

block m doesn t slide down 1 m g m 3 g 3 m 1 a m 9 M m mag m 55 A block of mass m kg is kept on a weighing machine in an elevator If the elevator is retarding upward by a ms 60 V the reading of weighing machine is in kgf mg m g m m 2 m g a 59 Se 4 m g a 2

A long U tube contains mercury and oscillates with time period T 2 s When 80 g of water is poured in one arm time period becomes T2 3 s The mass of mercury in tube in grams is PARAR

A vessel of volume V and thermal coefficient of linear expansion a is completely filled with a liquid The liquid does not overflow on heating The thermal coefficient of volume expansion of liquid is 1 V a V 3 G 2 V V a 4 3 a

An electron is accelerated through a potential difference of 10 000 V Its de Broglie wavelength is nearly m 9 x 10 31 kg NEET 2019 1 12 2 x 10 13 m 3 12 2 10 14 m 2 12 2 x 10 12 m 4 12 2 nm

The photoelectric threshold wavelength of silver is 3250 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 15 eVs and c 3 x 108 m s 1 NEET 2017 1 6 x 105 m s 1 2 0 6 106 m s 1 3 61 x 10 m s 1 4 0 3 x 106 m s 1

Angle 8 rotated by a particle in circle varies with time t as 0 2t 1 O Average angular velocity between t 0 to t 1 second is 1 rad sec Average angular velocity between t 0 to t 1 second is 2 rad sec Magnitude of angular acceleration at t 2 sec is 12 rad sec Particle changes its direction of angular velocity once after t 0

please explain it through the diagram that if a third polari zer she is placed in between the A and B then if the angle between a and b is theta then how the angle between Ba nd C is also theta Unpolarized light of intensity I is incident on a system of two polarizes A followed by B The intensity of emergent light is I 2 If a third polarizer C is placed between A and B the intensity of emergent light is reduced to I 3 The angle between the polarizers A and C is 0 Then A B C D cos 0 cos 0 1 4 cos 8 1 4 1 2 3 2 2

A ceiling fan is rotating with a frequency of 3000 rpm If we switch off the supply it stops after 30 seconds with a constant angular acceleration then The initial angular velocity is 100 rad sec 10T rad s 3 The average angular velocity is 50 rad sec The average angular acceleration is Total number of revolution made by the celing fan will be 750

A particle of mass m attached to one end of a thin light inextensible string moves with speed v in a circle of radius ro in free space Calculate the work required to reduce the radius from ro to r by pulling the other end of the string through a smooth tube that is perpendicular to the plane of the circle Express the result in terms of m Vo To and r