Physics Questions

1 V 2 2V 3 4V 4 2V 19 9 Two metallic concentric shells are shown Questi closing the switch charge on inner shell is charge on outer shell is 2Q Potential at point A is V What will be potential at same point after closing the switch 2a 1 V 3 MI4 2 2V ilm 1 V fava 1 V Ce 2 2V 16 2a 3 4V en 4 2V 20 2 2V

Four persons P Q R and S are initially at the four corners of a square of side d Each person now moves with a constant speed v in such a way that P always moves directly towards Q Q towards R R towards S and S towards P The four persons will meet after time 1 2 3 2v 3d 2v

63 Two particles undergoes perfecting inelastic collision as shown in the figure The final speed of the bodies J 10 m s 2kg 1 7 m s 3 3 m s O 3kg 5 m s 2 4 m s 4 1 m s A small sphere undergoes vertical circular moti

PASSAGE In an ac circuit it is containing resistance of 15 ohm and inductance of 0 3H in series with 50Hz ac supply voltage If the voltage across resistance and inductance is 10 volt and 15 volt respectively Then determine following unkown parameters Choose the correct options Marks Calculate the power factor of the circuit OPTIONS 0 157 0 176

A particle revolving in a circular path completes first one third of circumference in 3 s while next one thin in 2 s The average angular velocity of the particle A rad s B Trad s 5 K rad s 15 C D 27 15 47 15 rad s

3 Current i is carried in a wire of length L If the wire is turned into an equilateral triangular coii the maximum magnitude of torque in a given magnetic field B will be il B iL B il B 9 2 3 3 2 12 3 1 il B 6 3

A particle is projected from ground at an angle wi horizontal with speed u The ratio of radius 0 curvature of its trajectory at point of projection radius of curvature at maximum height is 1 1 sin ecose 2 cos 0 3 1 sin 0 1

LEADER TEST SERIES JOINT PACKAGE RANK BOOSTER COURSE EET UG 2021 04072021 Space for Rough Work 2 Decay rate for a certain mass of a radioactive substance measured at diffrent times varies with time as shown in fig countrate at t 8 hr will be Decays sec 200 150 100 50 N ALLEN 42 t hr U DA f

17 The expression for the equivalent capacitance of the system shown is A is the cross sectional area of one of the upper plates AL klo ga A O 3d 1a1 1140 a d da 3a 2 4 sofa 3A 0 d 6 A80 KAZC 4 3d 3d keq KAGO

A uniform sphere of charge of radius 1 0 m and charge per unit volume p 2 0 C m is kept with its centre at the origin A spherical cavity of radius 0 25 m with centre on the x axis at x 0 75 m is created in the cavity The electric field at point 0 75 m 0 2 m 0 m inside the cavity will be O 18 x10 NC 67 i 3 j N C O 9 0 2 N C

The refractive index of the glass prism shown in the figure is 2 for green light a ray of cyan colour light is incidence a tp on the face bc of the prism from which side would the light emerge Given the critical angle for blue colour is gr eater than 15 50 The refractive index of the glass prism shown in the figure is 2 for green light A ray of cyan colour light is incident at P on the face BC of the prism From which side would the light emerge Given the critical angle for blue colour is greater than 15 CYAN B C 60 45

0 Consider the two statements related to circular motion in usual notations A In uniform circular motion and a are always mutually perpendicular B In non uniform circular motion v and a are always mutually perpendicular 1 Both A and B are true 2 4 Both A and B are false A is false but B is true

A photon of energy 4 eV is incident on a metal surface whose work function is 2 eV The minimum reverse potential to be applied for stopping the emission of electrons is 2 4V 4 8V 2V 3 6V TI

The horizontal component of earth s magnetic field at a place is 4 x 10 4 T and dip is 45 A metal rod of length 20 cm is placed in north south direction and is moved at constant speed of 5 cm s towards East What is e m f induced in the rod O 4 x 10 6 V O 2x 10 4 V 4 x 10 5 V 3 x 10 6 V

52 Which of following statements is TRUE 1 Any physical quantity which has magnitude and direction both must be a vector 2 A vector does not change if it is rotated through an arbitrary angle 3 Component of a vector does not depend on the orientation of the axes 4 A vector won t change if it slides parallel to itself

According to Lenz s law of electromagnetic induction The induced emf in the direction opposing the change in magnetic flux The relative motion between coil and magnet produces no change in magnetic flux in any case Only magnet should be moved towards coil Only the coil should be moved towards magnet

36 A coil of inductance 5H is joined to a cell of emf 6V through a resistance of 10 2 at t 0 The potential difference across the coil at time t In 2 sec is 1 3V 3 0 75 V 2 1 5 V 4 4 5 V

Projectile A particle is projected at angle 0 with horizontal from ground The slop m of the trajectory of the particle varies with time t as 1 m m 2 t f n m avo 3 m wol S 8

A particle of mass m is attached to three identical springs A B and C each of force constant k as shown in figure If the particle of mass m is pushed slightly against the spring A and released then the time period of oscillation is ellele B 90 0lm A rellele mmmmm

What is the fundamental frequency of a musical instrument if the frequency of the 5th overtone is 240 Hz Instruction Write only number Do not write unit

A man moves in an open field such that after moving 10 m on a straight line he makes a sharp turn of 60 to his left The total displacement just at the start of 8th turn is equal to 1 12 m 2 15 m 3 17 32 m 4 14 11 m

63 A particle accelerates from rest at a constant rate for some time and attains a velocity of 8 m Afterwards it decelerates with the constant rate and comes to rest If the total time taken is 4 secon the ratio of the distances travelled during acceleration and during deceleration is 4 1 3 2 2 1 1 1 1 3 1 2

Two masses m and 2m are connected by a string passing over a pulley fixed at the top of an inclined plane The first mass moves vertically downwards drawing the second up the incline If the angle of inclination is e and the coefficient of friction is u the acceleration of the system is less than it would be if the plane were smooth by an amount 1 2 g 3 1 2 sine g 3 2 4 2 3 2 3 sin eg g cose

The figure shows a network of currents The magnitude of currents is shown here The current I will be A a 3 A Oa is correct Ob is correct Oc is correct Od is correct b 9 A 10A 6 A c 13 A 2 A d 19 A

Focal length of a thin convex lens is 30 cm At a distance of 10 cm from the lens there is a plane refracting surface of refractive index Where will the parallel rays incident On lens converge a At a distance of 25 cm from the lens b At a distance of 27 5 cm from the lens c At a distance of 40 cm from the lens d At a distance of 45 cm from the lens 3 S 2 A

If an aircraft travels with a speed of 325 m s in air at 25 C its Mach number will be Use Speed of sound in air at 0 C 331 m s Select one O a 0 58 b 0 87 c 0 94

Water is filled to a height of 18 0 m deep in a storage tank whose top is open to the atmosphere What are the absolute pressure at the bottom of the tank Use Acceleration due to gravity 9 8 m s Density of Water pwater 1000 kg m Atmospheric Pressure Patm 1 01 X10 Pa Select one a 2 77 x 10 Pa b 1 76 x 10 Pa 5 c 2 19 x 10 Pa

The specific heat of vaporization of water is about 2 260 kJ kg What is the energy needed to vaporize 0 65 kg of water Select one O a 3477 J O b 1469000 J c 1469 J

Two particles A and B start moving with velocitie 20 m s and 30 2 m s along x axis and at an angl 45 with x axis respectively in xy plane from origin The relative velocity of Bw r t A 1 101 30 m s 2 30 10 m s 3 301 20 21 m s 4 30 5 Mpa

11 A particle performing SHM is found at its equilibrium at t 1 sec and it is found to have a speed of 0 25 m s at t 2 sec If the period of oscillation is 6 sec Calculate amplitude of oscillation A C V Aw sin art 3 2 O E m m 3 B m 4 3 8 D

A helicopter has a mass m and maintains height by imparting a downward momentum to a column of air defined by the slipstream boundary as shown in the figure The propeller blades can project a downward air speed v where the pressure in the stream below the blades is atmospheric and the radius of the circular cross section of the slip stream is r Neglect any rotational energy of the air the temperature rise due to air friction and any change in air density 1 mg C Power of engine A v for equilibrium mg mg 2r V TP B v 2 r mg p for equilibrium for equilibrium D Power of engine mg mg p for equilibrium

An insulated sphere of radius R has a uniform 44 R volume charge density p The electric field at a point P inside the sphere at a distance r from the centre is 1 Rp 380 rp 2 30 3 Zero 4 rp 3E0 P farg pufaga a m e Rp 3E0 rp 300 3 Zero rp 300 Telegram ne question paper r feerd

If the natural frequency of a string is 250 Hz the wavelength of the sound wave produced will be Use Speed of sound 340 m s Select one a 1 36 m b 2 48 m c 3 40 m

61 15 The surface tension of a liquid is given as T a02 be where a and b are constants and 9 is absolut temperature Dimensions of a and b are 1 M LT K M L T K 3 M T K2 M T K TRUE 2 MIT K2 MITK 4 MILZTK MILT K2

A cylinder of radius R and length L is placed in a 45 uniform electric field E parallel to the cylinder axis The total flux from the surface of the cylinder is 1 2 R E 2 R E 3 R R E 4 zero Tea and gas de of a gen UAS UNGHA TAI 1 2TR E 2 R E 3 R R E 4

Consider the four statements given below about the function f x x x in the range x o Which one of the following statements is correct P the plot of f x versus x has two maxima and two minima Q the plot of f x versus x cuts the x axis at four points R the plot of f x versus x has three extrema S no part of the plot f x versus x lies in the fourth quadrant Pick the right combination of correct choices from those given below a P and R b R only c R and S d P and Q

Choose incorrect statements An inductor of inductance L capacitance C and resistance R are connected in series to a variab sinusoidal voltage supply whose frequency is variable but rms voltage is constant At resonance Average power will be maximum III Impedence will be maximum II Average power will be minimum IV current and voltage will be in same phase A I and IV C I and III B II and III D II III and IV

A mass of 1 kg is suspended by a thread It is lifted up with an acceleration of 4 9 m s 2 and then lowered with an acceleration of 4 9 m s2 The ratio of tensions in first case to second cases is g 9 8 ms 2 1 O 1 1 3 1 1 3

A piston containing an ideal gas is originally in the state X see figure The gas is taken through a thermal cycle X Y X as shown The work done by the gas is positive if the direction of the thermal cycle is a clockwise b counter clockwise c neither clockwise nor counter clockwise d clockwise from X Y and counter clockwise from Y X P X Y

If work done in increasing the size of rectangular soap film with dimensions 8 cm x 3 75 cm to 10 cm x 6 cm is 2 10 J The surface tension of film in newton per meter is 2 1 x 10 2 1 65 x 10 2 3 3 x 10 2 2x 10

1 THE FORCE EXPERIENCED BY A POSITIVE CHARGE q MOVING WITH A VELOCITY V PERPENDICULAR GIVEN BY TO THE DIRECTION OF MAGNETIC FIELD B IS O qvB OqvB O Zero O 1 2qvB 1 point

A ball is projected from ground at angle 0 with the horizontal After t 1 s it is moving at 45 with the horizontal and after t 2 second it is moving horizontally What is speed of projection of ball g 10 m s 10 2 m s O 10 3 m s 20 m s 10 5 m s

An object moves along the x axis according to the equation x 2 80 2 00 3 00 where x is in meters and t is in seconds a Determine the average speed between t 2 80 s and t 4 10 s m s b Determine the instantaneous speed at t 2 80 s m s Determine the instantaneous speed at t 4 10 s m s c Determine the average acceleration between t 2 80s and t 4 10 s m s d Determine the instantaneous acceleration at t 2 80 s mys Determine the instantaneous acceleration at t 4 10 s m s

The small piston of a hydraulic lift has a cross sectional area of 3 cm and its large piston has a cross sectional area of 200 cm What force must be applied to the small piston to lift a load of 12 0 kN Select one O a 1 80 N b 18 0 N c 180 N

The hyperfine splitting of the spectral lines of an atom is due to a the coupling between the spins of two or more electrons b the coupling between the spins and the orbital angular momenta of the electron c the coupling between the electron spins and the nuclear spin d the effect of external electromagnetic fields

Q is ahead of P by 350 m A car A is travelling along a straight level road with a uniform speed of 60 km h It is followed by another car B which is travelling uniformly at 70 km h When the distance between them is 2 5 km the car B decelerates at 20 km h Where will B catch up with A

The galvanometer shown in figure has resistance 5 0 Main current of 6 A passes in circuit as shown If current through galvanometer is lg then 6 A 10 10 17 15 5 4 Q wwww 192 5 V A when switch S is closed A when switch S is closed A when switch S is open lg 0 A when switch S is open S

d 1 1 3 A motor car is moving towards a vertical wall The driver observes that the frequency of the sound of his horn changes from 440 Hz to 480 Hz when he hears the reflected sound from the wall If the velocity of sound is 330 m s what is the speed of the car

STAT A cubic cell consists of two atoms of masses m and m m m with m and m atoms situated on alternate planes Assuming only nearest neighbor interactions the centre of mass of the two atoms a moves with the atoms in the optical mode and remains fixed in the acoustic mode 1 b remains fixed in the optical mode and moves with the atoms in the acoustic mode c remains fixed in both optical and acoustic modes BUR d moves with the atoms in both optical and acoustic modes

A particle P is formed due to a completely inelastic collision of particles x and y having de Broglie wavelengths y and respectively If x and y were moving in opposite directions then the de Broglie wavelength of P is 9 Apr 2019 I a Y Y b YxYV Y Yy X KY