Physics Questions

A steel wire of length 2 m is stretched through 2 mm What is elastic potential energy stored in a wire of cross sectional area 4 mm in stretched condition Y 2 x 10 1 Nm 0 8 J O 1 2 J 2 4 J 1 6 J

Find accel Acceleration of free fall is g 7 An arrangement setup inside a lift is shown in the figure The pulleys and threads are ideal and masses of the blocks are m and M M 2m Find minimum acceleration of the lift for which the thread remains taut and both the blocks accelerate in the same direction relative to the ground Acceleration due to gravity is g are of equal mass the m M

A 100 00 kg roller coaster car is pressed against a spring of constant 1 425 N m and compresses it 5 00 meters It is then released and rolls up an inclined portion of the track How high up the incline will car roll before coming to a stop

The velocity distribution in a viscous flow over a plate is given by u 4y y for y 2m where u is velocity in m s at a point which is at a distance y from the plate If the coefficient of dynamic viscosity is 1 5 in SI units Determine the shear stress at y 0 in N m

4 atoms contains negatively charged particles 32 Graph of total number of a particles scattered at different angles is Number of a particles Number of 14 20 160 0 20 160 0 a particles 4 32 fafan 19 Lin 40 70 Ita F 14 10 42 70 2 F341 20 160 0 20 160 0 E

In Young s double slit experiment the intensity at a point where the path difference is being the wavelength of the light used is I If lo denotes the maximum intensity then is equal to O 1 2 O 3 2 O 1 2 O 3 4

A gyroscope spins with its tip on the ground and is spinning with negligible frictional resistance The disk of gyroscope has mass 0 3 kg and is spinning at 2 0 rev sec Its center of mass is 5 0 cm from the pivot and the radius of the disk is 5 0 cm What is the processional period of the gyroscope O 5 0 sec O 3 0 sec O2 0 sec O 2 5 sec

A current i flows in a thin wire in the shape of a regular polygon with n sides The magnetic induction at the centre of the polygon when n is R is the radius of its Circumcircle 1 Moni tan 2TR 6 llo i T 2 Moni T tan 2TR n

For froyoun 1 One mole of an ideal monatomic process described by the equation pV3 constant The heat capacity of the gas during this process is NEET 201 312 a R 5 b R 2 c 2R spes gas undergoes a al d R

Secondary output of a transformer is 12 V for 220 V primary input Which of the followin statements is true for this transformer a It is a step up transformer with turns ratio greater than 1 b It is a step up transformer with turns ratio less than 1 c It is a step down transformer with turns ratio less than 1 d It is a step down transformer with turns ratio greater than 1 8 2

A bead moves along a straight horizontal wire of length L starting from the left end with velocity vo retardation is proportional to the distance that remains to the right end of the wire If bead reaches right end of the wire with velocity then initial acceleration at left end of wire will be 2 1 3v 2L 2 Vo 6L 3 3v 6L 4 NO 4L

The plates of a parallel plate capacitor are separated by d cm A plate of thickness t cm with dielectric constant k is inserted and the remaining space is filled with a plate of dielectric constant k If Q is the charge on the capacitor and area of plates is A cm each then potential difference between the plates is 4 Q t B C A k Q Ak Two identical capacitors have A d t k k 4 Q k A t k d t D Q k A t d t k

The mean weight of 150 students in a certain class is 60 kilograms The mean weight of boys in the class is 70 kilogram and that of the girls is 55 kilograms Find the number of boys and number of girls in the class

lucting shells A and B of radil r and 2r respectively They are given charge Q and 2Q respectively as shown A 3 Q 2Q After the switch is closed what is the charge on inner surface of shell B 1 Zero B 2 Q 4 3Q 2 Medic

162 If wind is blowing from source side to observer side what will be effect occur on the difference between apparant freq to original freq during relative motion between source and observer A Decreases B Increases C Remain constant D Can t say

Two bodies M and M are connected by a light string passing over a light smooth pulley at the end of an incline The mass M lies on incline and mass M hangs vertically The system is at rest M Calculate the angle of incline and the force exerted by the incline on the body of mass M

A thin walled glass tube of radius 0 5 cm is dipped vertically in the water of surface tension 70 dyne cm The force required to take it out from the water is Mark for review later 44 10 5 N O 44 x 104 N 4 O 2 4 10 4 N O 0 44 x 10 6 N

Q 8 a c A stone thrown from the top of a building is given an initial velocity of 20 0 m s straight upward Determine the time in seconds at which the stone returns to the height from which it was thrown g 9 8m sec 4 08 4 44 b d 3 45 5 32

4 The following figure shows the electric lines of force emerging from a charged body If the electric field at A and B are EA and EB respectively and if the displacement between A and B is r then B DE F 2

attempted questions will be con ned for marking A current carrying wire AB of length 2nR is turned along a circular arc as shown Then magnetic field at O A B B It 0 Hoi 2 0 Correct Answer My Answer

why is the Reynolds number taken as 2000 while as per ERT the laminar or steady flow is less than 1000 plit increases Discuss qualitatively 10 26 a What is the largest average velocity of blood flow in an artery of radius 2x10 m if the flow must remain lanimar b What is the corresponding flow rate Take viscosity of blood to be 2 084 x 10 3 Pa s

16 An alternating emf of frequency v 2 LC is applied to a series L C R circuit For the frequency of the applied emf 1 the circuit is at resonance and its impedance is made up only of a reactive part 2 The current in the circuit is in phase with the applied emf and voltage across R equals the applied emf 3 the sum of the potential difference across the inductance and capacitance equals the applied emf which is 180 ahead of phase of the current in the circuit 4 the quality factor of the circuit is 1 CR 16 faza fauc arafu v OL R or and this is measure of the voltage magnification produced by the circuit at L C R enginfor 1 t 2 a ft RIGH fan fav 3 du fawaink an die T 180 4 factual que CL R 2x LC all CR TEE he

current phasor I is V 1 2 V sin oot L i sin oot m V sin oot m i sin wt 2 m wt TC 2 Soot behind the voltage phasor V 3 Both 1 and 2 4 Neither 1 nor 2

36 A mercury drop of radius 1 0 cm is sprayed inte 10 droplets of equal sizes The energy expender in this process is surface tension of mercury is equal to 32 x 10 Nm 1 3 98 x 104 J 2 8 46 x 104 J 3 3 98 x 10 J

The period of revolution of planet A around the sun 8 times that of B The distance of A from the sun i how many times greater than that of B from the sun 1 4 2 3 3 4 523 par 10 2 X 13

Magnetic field intensity is defined as Magnetic moment per unit volume 2 Magnetic induction force acting on a unit magnetic pole Number of lines of force crossing per unit area 4 Number of lines of force crossing per unit volume

Two metal plates form a parallel plate capacitor of capacitance C The distance between the plates is d A metal sheet of thickness d 2 and of the same area is introduced between the plates and capacitance becomes C The ratio of C and C is af 2 1 1 2 b d 3 1 5 1

8 Radii of conductors 1 2 as shown below are r 2r If the resistivity of their materials are same and equal to p then current drawn from the battery will be 2 4 r E 3 1 E 58 27 2 1 E

tric experiment is performed at two different light intensities I and 1 1 Choose the correct graph showing the variation of stopping potential versus frequency of light 1 12 1 2 12 4 3 v fi fi L fo I 4 None of these

3 12 cm s 4 8 cm s When a wave travels in a medium the particle 42 displacement is given by y asin 2x bt cx where a b and c are constants The maximum particle velocity will be twice the wave velocity if 1 c 3 b ac 2 a 4 b ac 3 12 cm s 2 y a sin 2x bt cx a fe a bac C n din n an yu m afa fazen Me 1 c 4 8 cm s 3 b ac 2 na 4 b ac

Given a current carrying wire of non uniform cross section Which of the following is constant through out the wire a O Current and drift speed b O C Drift speed only O Current only

A smooth narrow tunnel is dug along the chord of earth The time period of vibration of a small ball dropped from one end of the tunnel is AVE f 1 60 minute 2 123 minute 2 84 6 minute 4 30 minute

A ball of mass 1 kg collides perpendicularly on a smooth stationary wedge of mass 2 kg kept on a smooth horizontal surface The coefficient restitution is e 1 2 The velocity of ball after the collision is m s The value of K is ma V 10 m s 0 30 M

Due to capillary action water rises to a height of 1 16 3 cm in a capillary of length 18 cm above the water level If the tube is cut at height of 12 cm 1 Water will come as fountain from the capillary tube 2 Water will stay at a height of 12 cm in the capillary tube but radius of curvature at top will increase 3 Water will stay at a height of 12 cm in capillary tube but radius of curvature at top will decrease

24 Two concentric and coplanar circular coils have radii a and b a as shown in figure Resistance of the inner coil is R Current in the outer coil is increased from 0 to i then the total charge circulating the inner coil is Hoia 2Rb a c Hoi b 2a R b ats b Hoiab b b 2R d Ho ib 2 R

Question 30 In the following figure the diodes which are forward biased are A B A B and D C only C and A R and D SV 10V R A C 9 10V R SV 10V R B D R SV

Charge is uniformly distributed with volume charge density p inside a very long cylinder of radius R If the potential difference between the surface and the axis of cylinder is PR n o find the value of n

A piece of wood is floating in water kept in a 34 bottle The bottle is connected to an air pump Neglect the compressibility of water If more air is pushed into the bottle from the pump the piece of wood will float with 1 Larger part in the water 2 Lesser part in the water 3 Same part in the water as earlier 4 It will sink impletely filled with

SolveLancer Test Consider these statements i The reason of thermal expansion is asymmetry in potential energy curve ii Coefficient of expansion of invar is very high iii All specific heats found to vary at the low temperatures iv Specific heats of saturated water vapours is negative Select correct option SolveLancer Test a i and ii true b Only ii true c iii and iv true d All are false a b

The figure below shows an initially stationary block of mass m on a floor A force of magnitude F 0 530mg is then applied at upward angle 8 24 a What is the magnitude of the acceleration of the block across the floor if the friction coefficients are us 0 595 and Uk m s 0 510 b What is the magnitude of the acceleration of the block across the floor if the friction coefficients are us 0 395 and 0 305 m s

A long current carrying wire having current Iis placed along z axis directed outside the plane Point A B and Care shown in figure Choose the correct options a 0 C 18 di 4 Hol B dl Y Bdl 3 g 8 B dl E A a a B a a along the path ADB as shown 18 3 3 dl 3 along the straight path AC as shown along the path BEC as shown Hol along the path ABCA as shown

4 0 12 15 Two exactly similar wires of steel and copper are stretched by equal forces If the total elongation is 2 cm then how much is the elongation in steel and copper wire respectively Given Y 20 1011 dyne cm2 Ycopper 12 x 10 1 dyne cm 1 1 25 cm 0 75 cm 2 0 75 cm 1 25 cm 3 1 15 cm 0 85 cm 4 085 cm 115 cm

175 A jet air plane travelling with a speed of 500 km h ejects its products of combustion with a speed of 1500 km h relative to the jet plane The speed of the latter with respect to an observer on the ground is 1 1500 km h 3 1000 km h 2 2000 km h 4 500 km h

A particle moves along x axis as x t t 2 t 2 Which of the following is true A The initial velocity of particle is 4 B The acceleration of particle varies with ti C The particle is at origin at t 0 D None of these A

T A particle starting from the origin 0 0 moves in a straight line in the x y plane Its co ordinates at a later time are 3 3 The path of the particle makes with the x axis an angle of a 30 c 45 e 60 d 0

A steel wire of length 20 cm and uniform cross section 1 mm is tied rigidly at both the ends The temperature of the wire is altered from 40 C to 20 C Coefficient of linear expansion for steel a 1 1 x 10 5 C and Y for steel is 2 0 10 1 N m The change in tension of the wire is a 2 2 106 newton b 16 newton c 8 newton d 44 newton 1 0 X

29 A charged particle is placed at the centre of cube o length L ABCDEFGH Another same charge q is placed at a distance L from O Then the electric flux through ABCD is gen F Eo 0 60 E q C L q

3 31 In the circuit shown in figure 3 387 the voltmeter is having a resistance 400052 Find the percentage error in reading of this voltmeter AI 5000 300V 40000 V 100002 wwwwww un at

7 12 SolveLancer Test A body of mass m moving at velocity u collides with a body of mass m which is initially at rest The second body is moving with a velocity of u in its initial direction after the collision Determine the kinetic energy lost by the first body following the collision Restitution coefficient SolveLancer Test a 15 mu 16 b 16 c 1 5 mu 32 9 d mu 32 a mu b

3 tan 1 4 4 tan 2 38 A man moves on a horizontal road towards east at a speed of 1 km h and the rain appears to him falling vertically at a speed of 2 km h The actual speed of the rain is 1 1 km h 3 3 km h 2 2 km h 4 5 km h and its