Physics Questions

An inductor coil stores 32 J of magnetic field energy and dissipates energy as heat at the rate of 320 W when a current of 4 A is passed through it The time constant of circuit when this coil is joined across ideal battery 1 0 1 sec 2 0 2 sec 3 0 3 sec 4 0 4 sec 21 2 3 4

The current and voltage function in an AC circuit are I 100 sin100t mA V 100 sin 100t 10 3 volt the power dissipated in the circuit is 1 10 W 2 2 5 W 3 5 W 4 5 kW

A 2uF capacitor is charged to 100 V After disconnecting the battery a 20 mH coil is then connected across the charged capacitor The capacitor discharges through the inductor and the current in the circuit is oscillatory Maximum current in the circuit assuming zero resistance of the coil is 1 0 5 A 2 0 75 A 3 1 A 4 1 5 A 31

TARGET PRE MEDICAL 20 A 10 kg mass is resting on a horizontal surface and horizontal force of 80 N is applied If 0 2 the ratio of acceleration without and with friction is g 10 m s CAREER INSTITUTE KOTA RAJASTHAN 1 2 4 2

A rectangular loop has a sliding connector PQ of length and resistance RS and it is moving with a speed v as shown The set up is placed in a uniform magnetic field going into the plane of the paper The three currents I I and I are P RO 1 1 1 www 3 I I Blv 6R 2 1 1 Blv 3R RO I Blv R Imm Blv Blv 3R I 2Blv R 2Blv 3R www RO 1 19

HOTS Problem 1 Four persons K L M and N are initially at rest at the four corners of a square of side d Each person now moves with a uniform speed v in such a way that K always moves directly towards L L directly towards M M directly towards N and N directly towards K Show that the four persons meet at a time dlv Solution All the four persons will meet at the centre O of the square Each person covers a displacement 1 Problems on Higher Order d d 2 Component of velocity v towards O v cos 45 v 2 Required time S V t K N d 2 v 2 V 45 v cos 45 Fic

In a series LCR circuit the frequencies f and 1 f at which the current falls to 1 current amplitude at resonance are separated by frequency interval R 2 2 21 VLC of the 3 VLC 4 RC 29

9 Two charges q and 4q are 1 m apart What are the location magnitude and sign of a third cha placed so that the entire system is at equilibrium NCERT 10 Two similarly and equally charged identical metal spheres A and B repel each other with a for

Box k A semi circular current carrying wire having radius R is placed in x y plane 2R with its centre at origin O There is non uniform magnetic field B here Bo is ve constant is existing in the region The magnetic force acting on semi circular wire will be along A C x axis PA y axis La som en adi voi eixe n adl B D y axis x axis R 0 0 Z R 0 0 X

here is a negative marking of 1 Mark No marks will be awarded if you leave question unattempted T A block of mass m is attached with a spring of spring constant K It is lowered slowly from the natural length of the spring and left at equilibrium Find work done by the external agent A W mgh C W m g 2K B W D W 2 m g 2K 2m g K

There is a uniform magnetic field B normal to the xy plane A conductor ABC has length AB parallel to the x axis and length BC parallel to the y axis ABC moves in the xy plane with velocity vi vyj The potential difference between A and C is proportional to A 1 v l V l 2 v l V l 3 V Vyl B

A 4 R 4 R A long straight metal rod has a very long hole of radius a drilled parallel to the rod axis as shown in the figure If the rod carries a current i find the value of magnetic induction on the axis of the hole where OC c Hoic A b a Hoic B 2 b a C Hoi b a 2 c D Moic 2 a b

Two boats A and B having same speed in still water are moving in a river A moves normal to river current as observed from ground B moves normal to river current as observed from the river frame Then A For a ground observer B is moving faster than A B For a ground observer A and B are moving with same speed C For an observer in river frame B is moving faster than A D For an observer in river frame A and B are moving with same speed

The inductance of a coil is 60 H A current in this coil increases from 1 0 A to 1 5 A in 0 1 second The magnitude of the induced e m f is 1 60 106 V 2 300 x 104 V 3 30 x 104 V 4 3 x 104 V

3 In an A C sub circuit as shown in figure the resistance R 0 2 2 At a certain instant VA VB 0 5 0 5 A and current is increasing at the rate of A At 1 0 01 H 2 0 02 H A L mmmmmmm 8 A s The inductance of the coil is R 3 0 05 H 1 B 4 0 5 H

A particle of mass m moves with a velocity v a x where a is constant Find the total work done by all the forces during a displacement from x 0 tox d 1 m 2 ma d 1 M

3a below its A particle is moving with constant speed u inside a fixed smooth hemispherical bowl of radius a describes a horizontal circle at a distance 2 centre Then The radius of the circular motion is The value of u is ag 2 3 mg The normal reaction of the spherical surface on the particle is The magnitude of the resultant force acting on the particle is zero in an inertial frame

A bullet is fired with a velocity of 500 m s in a direction 20 above the horizontal Given that its acceleration is a gj where g 9 8 m s and it is initially at 0 0 find its velocity v at any time t seconds

Position time graph of a particle moving in a straight line is as shown in figure Select the correct alternative s X C 0 A Work done by all the forces in region OA and BC is positive Work done by all the forces in region AB is zero Work done by all the forces in region BC is negative B Work done by all the forces in region OC is zero t

index of medium I and medium II can be changed and hypothetically their ranges are given by 1 and 1 0 Medium II H2 Medium I 40 H1 8 80 8 An experiment is performed keeping i 60 as constant First 2 is increased from 1 to infinity keeping 1 and deviation is calculated Then the refractive index of medium I is increased from 1 to infinity keeping 2 1 and deviation is noted Now an approximate graph between and k 1 2 is plotted which is shown in the figure Read the above passage carefully and answer the following question Region i 60 1 1 0 2 0 1 5 I I I N 1 ko Interface Region The value of ko is equal to Region III k

The sun orbits the centre of the galaxy Milky Way in almost circular path of radius R in a period T and the earth also orbits the sun in an almost circular path of radius r in a period t Assume whole mass of the galaxy concentrated at its centre and find an expression for the ratio of the mass of the galaxy to that of the sun a R G T B L R t 3 T BA r a R TY

Answer of 1 is option 2 of 2 is option 3 xplain 10 A steady eletric current is flowing through a cylindrical wire a the electric field at the axis of wire is zero c the electric field in the vicinity of wire is Zero 1 a b c 2 b c b the magnetic field at the axis of wire is zero d the magnetic field in the vicinity of wire is Zer 3 only c 4 only b For the hollow thin cylinderical current carrying pipe which statement is correct 1 magnetic field inside the pipe is not zero 3 electric field out side the pipe is zero 2 magnetic field out side the pipe is zero 4 electric field on the surface of pipe is zero

tan 13 6 is at a point P whose coordinates are Bird observes two points P and P 1 m 2 m 0 m and 1 m 1 m 4 m 0 it starts flying in a plane of three ant speed of 5 ms in a direction might line P P till it sees P and P late t tion is shown in Fig 4 95 The on perpendicular to line P P point Q in time after starting sees P and P as collinear m 4 m 7 B 9 4 95 26 6 e P 1 m 2 m 0 m 2 67 m 4 583 Time taken by bird to reach the point Q will be d 2 67 0 5346 s V 5 3 kmh finds that wind seems to blow from north On Problem 4 A person travelling eastward with a speed of doubling his speed the wind appears to flow from north east Find the magnitude of the actual velocity of the wind Solution The situation is shown in Fig 4 96 North West Wind 6 km h 3 km h 45 Fig 4 96 Let the wind velocity be v 90 8 North East Man East of wind makes an

In the below figure if the coefficient of friction between 2 kg and incline is u 0 2 and that between the block of mass 4 kg and the incline is 0 30 The acceleration 2 kg block is g 10 m s 4kg 2kg 30 1 2 7 m s 2 10 m s 4 11 m s 3 5 m s Aeroplane are stream lined to reduce 1 Fluid friction 3 Kinetic friction 2 Sliding friction 4 Limiting friction

Two blocks of masses 2 kg and 3 kg are connected by massless spring and are placed on smooth surface If impulse is given to 2 kg block and block starts moving with velocity 10 m s in ve x direction then velocity of 2 kg block w r t centre of mass is 1 4 m s ve x direction 2 6 m s ve x direction 3 4 m s x direction 4 6 m s x direction

A chain of mass M and Length L is held on a frictionless table in such a way that part is n hanging below the edge of table Calculate the work done to pull the hanging part of the chain Mgl 2n Mgl 2n 4 MgL 2n Mgl 2n

A merry go round rotates from rest with constant angular acceleration a Ratio of time to rotate first 2 revolutions and next 2 revolutions is 2 2 1 1 4 1 2 1 1 1 3 2 1

Two different simple harmonic oscillators have the same natural frequency f 2 60 Hz when they are on the surface of the Earth The first oscillator is a pendulum the second vertical spring and mass If both systems are moved to the surface of the moon g 1 67 m s2 what is the new frequency of the pendulum Submit Answer Tries 0 20 Calculate the new frequency of the vertical spring and mass

A rigid rod of length is sliding At some instant position of the rod is as shown in the figure End A has constant velocity vo At t 0 y l y wall B 0 X A floor X Component of velocity of end B along the length of the rod as a function of time t is Graph of y as a function of time t is a parabola Velocity of end B as a function of time t is vo t y Graph of y as a function of time t is an ellipse

1 kg of water at a temperature of 353 K is mixed adiabatically with an equal mass of water at 293 K Find the change in entropy of the universe assuming the specific heat of water to be constant equal to 238 J kg K

In the figure pulleys are smooth and strings are massless m 1 kg and m kg To keep m at rest mass m should be m m m

ALLEN CAREER ISTITUTE MARJANTARE TARGET PRE MEDICAL 2022 A body of mass 10 kg is moving along a smooth inclined plane 0 60 with constant velocity through a distance of 10 m Then work done on the body by gravitational force is 1 500 J 2 500 3J 3 1000 31 4 1000 J

ET Part I cing an gth of en the Last Leap for NEET Part I A ray of light is incident on a prism of angle A and refractive index u will not emerge out of prism for any angle of incidence if 1 sin 3 A N 2 1 sin A 2 cos A 4 1 sin A Ray Optics and 27 A small air bubble is prose of a glass sphere Size of the outside is of 1 Same size 2 Bigger 3 Smaller 4 May be smal distance of c ho maximum angle of acceptance 28 An object is at concave mirro

33 In the given arrangement string and pulleys are massless and mass of wedge M following statements are correct Neglect friction every where Wedge m M 16g A Downward acceleration of m with respect to wedge is 21 4g B Acceleration of wedge with respect to ground is 21 C Acceleration of mass m with respect to ground is 4g 17 5g D Acceleration of wedge with respect to ground is 21 4m then which of th

A block of mass m is placed on a plank of mass M and given velocity V Friction between plank and ground is zero The coefficient of friction between the block and plank is and its value is such that block becomes stationary wit respect to plank before it reaches the other end Then m the work done by friction on the block is negative the work done by friction on the plank is positive the net work done by friction is negative net work done by the friction is zero Vo M

The pulleys and the strings are light and all surfaces are frictionless If accelerations of mass M and 2M are a and a respectively then 22 1 a 2a 3 a 3 O 2M M 2 2a 3 4 a 4a

mple 9 A magnetic dipole of magnetic moment M is placed on the axis of a current carrying circular lo of radius R at a distance x from the centre Find the force acting on the dipole

2022 NEET NURTURE PHASE I TO I INTERNAL TEST 06 23 09 2020 HAVE CONFIDENCE 100 SUCCESS YSICS A particle moves from 3 23 6k m to 141 13 9k m Under the action of force 41 3 3k N the work done on the particle is 2 100 J 1 10 J 2 1000

block of mass of 2 kg is at rest on rough surface Coefficient of friction between block surface is 0 4 A horizontal force F is applied on the block Variation of F is presented in figure Maximum speed in m s of block during the motion is vo then find value of Vo 5 FA 2kg 0 4 F 12N 4N t

For given figure ma is 30 kg mB mc 5 kg respectively All contact surfaces are smooth g 10 m s2 Select the correct statements B Tension in string is 30N Contact force between R and C is 20 N A Acceleration of block A B and C arc 1 m s 4 m s and 5 m s2 respectively O Contact force between B Ground is 350 N

act on a body in x direction find the work X done in displacing the body from x a to x 2a k is a positive constant If F 1 3 2a 4a k 2a 4a

A boat is being steered across a river flowing at 4 m s The river has a width of 100 m In each of the cases shown in List I the velocity of boat in still water is 2 m s In List II we indicated the possible values of time taken to cross the river Match them 1 11 IV List l The boat is being steered to minimize the time taken to cross the river The boat is being steered to minimize the drift The boat is being steered at an angle of 30 to the river flow The boat is being steered at an angle of 120 to the river flow O LP 11 S III RIV Q OP RIIDR IV Q LUIRIRIV Q OP Q R IV Q P Q R S T U List I 50 sec 58 sec 100 sec 120 sec 20 sec 40 sec

QR P S T XW this equation is V dimentionally correct where all the letters represent physical quantities then choose the incorrect statement s none is dimensionless If

In the circuit shown in figure the current measured by ammeter is 60V 1 2 1 A R 100 Question Type Single Correct Type 2 A V mmmm 50V 100V HH

K 48 The potential energy of a 1 kg particle free to move along x axis is given by U x 4 2 total mechanical energy of the particle is 2J Then the maximum speed in m s is 1 2 3 3 2 2 2 4 2 J The

Assuming human pupil to have a radius of 0 25cm and a comfortable viewing distance of 25cm the minimum separation between two objects that human eye can resolve at 500 nm wavelength is Question Type Single Correct Type 1 2 3 100 m 300 m 1 m

3 1 2 2 31 Dip circle is initially in magnetic meridian and then it is rotated by 30 If angle of dip in new meridian is 45 then angle of dip at same place in magnetic meridian is 1 0 2 2 3 0 1 4 2 0 3 2 0 1 2 4 0 the magnifying power of an Q 37 A glass radius 4 object i sphere then fin

If one surface of a biconvex lens is silvered then it behave as 1 A concave mirror of focal length 2 A concave mirror of focal length 3 A convex mirror of focal length R 4 2 R 2 R 4 2 4 A concave mirror of focal length R 2 2

For an electromagnetic wave propagating through vacuum the amplitude of electric field vector is 30 V m The maximum value of magnetic field is Only one correct answer A 2 8 T B C 3 T 0 1 UT i

The rest energy of an electron is 0 511 MeV The electron is accelerated from rest to a velocity 0 5 c The change in its energy will be 1 0 026 MeV 2 0 051 MeV 3 0 079 MeV 4 0 105 MeV