Physics Questions

A heavy rope is suspended from rigid support A wave pulse is set up at the lower end Then O The pulse travels with uniform speed O The pulse will travel with increasing spee The pulse will travel with decreasing speed The pulse cannot travel through rope

5 For a cell a graph is plotted between the potential difference V across the terminals of the cell and the current I drawn from the cell The e m f and internal resistance of the cell is E and r respectively ff VRI GIDI 1 E 21 050 215 V volt 2 0 1 5 1 0 0 5 21x 1 2 3 4 5 I amp 010 2 21x 050 ALE 21x

unit cell is 400 pm long If 48 edge of a atomic weight of the element is 120 and it s density is 6 25 g cm The crystal lattice is use N 6 x 102 1 Primitive 2 Body centered 3 Face centered 4 End centered et ses enfant 400 pm 20 an 6 25 g cm 1 f N 6 102 1 2 3 4 f fe fa

In the arrangement of parallel plate capacitor shown in figure dielectrics identical shaped with dielectric constant k 2 and k 3 are inserted If the capacitances are C and C respectively then ratio of C and C is A 2 K O 1 1 15 9 20 13 1 A 2 K 2 d 2 d 2

pEcost 20 20 3 Consider a conducting spherical shell of radius R with 33 4d Shell its centre at the origin carrying uniform positive surface charge density The variation of the magnitude of the electric field E r and the electric potential V r with the distance r from the centre is best represented by the graph Here dotted line represents potential curve and bold line represents electric field curve V r V r 3 E r V r E r 2 E r V r E r EADER TEST SERIES JOINT PACKAGE COURSE q fakta fa 1 r me decla te verfa fa 305 8 farga 30 faga fa faga faga fava V r 3 favaganten all B V r pEcos E r V r E r R 2 V r E r V r E r 0999DMD310320004

122 A parallel beam of light travelling in water refractive index 4 3 is refracted by a spherical air bubble of radius 2cm situated in water Assuming the light rays to be paraxial the position of the image due to refraction at the first surface is A 6cm from the first surface B 12 cm from the first surface C 3cm from the first surface D 10 cm from the first surface

A body starts from ous an initial velocity of Ims and moves along n anis under the action of a motor which Power P delivered by Varies with position 21 as shown Mbody 10 K AP watt 4W 2W 10M 2 Mettre Velocity of body at 2 10m is

16 If two jaw of vernier calliper are joined then vernier scale zero is on left of main scale zero and 4th vemier scale division coincides with a main scale division then find zero error If one division of main scale equals 1 mm and 10 vernier scale divisions equals 9 main scale divisions then 1 ve error of 0 4 mm 2 ve error of 0 4 mm 3 ve error of 0 6 mm 4 ve error of 0 6 mm 4 The 22 What show

73 When the u tube shown below is in rest th liquid stands at the same level in both the tub But as indicated a height difference h occurs w the system is given an acceleration a towards right Here h is equal to aL 1 2g L 2 2a a

A current of 1 mA is flowing through a copper wire How many electrons will pass a given point in one second e 1 6 10 Coulomb 1 6 25 10 9 2 6 25 101 5 3 6 25 10 1 4 6 25 108 1 2 3 4

4 Red light Microwaves X Ray Rad A square coil ABCD lying in x y plane with its centre at origin A long straight wire passing through origin carries a current i 2t in negative z direction The induced current in the coil is 1 Clockwise Alternating C YA B D 2 R d 2 Anticlockwise 4 Zero I

ectron is orbiting in a circular orbit under the influence of a constant transverse magnetic field of strength B Assuming that Bohr s postulate regarding th entum holds good for this electron find the kinetic energy of electron in n th orbit m mass of electron e magnitude of charge of electron CE KE KE nhBe 27 Me nhBe 12 me nhBe

The focal length of a concave mirror is 30 cm Find the position of the object in front of the mirror on axis so that the image is three times the size of the object 40 cm 20 cm 50 cm Both 20 cm and 40 cm are possible

Q18 A battery has e m f 4V and internal resistance r When this battery is connected to an external resistance of 2 ohms a current of 1 amp flows in the circuit How much current will flow if the terminals of the battery are connected directly 1 1 Amp 2 2 Amp 3 4 Amp 4 Infinite

P 1x105 T At place s to complete one vibration The value of the earth s horizontal field at that place is a 0 25 x 10 T c 0 66 x 108 T The length of a magnet is large compared to its width and breadth The time period of its oscillation in a vibration magnetometer is 2 s The magnet is cut along its length into three equal parts and three parts are then placed on each other with their like poles together The time period of this combination will be a 2s c 2 3s A b 0 36x10 6 d 1 2x10 6 T b 3 2 d S 3 magnet oscillating in a horizontal plane has a time a OQ sk b OQ c 00 d 0 5 The inte m

Q6 The equivalent resistance across AB is 1 2R 2 R 2 3 4R 3 4 3R 2 1 R H 2R R www www 2 by B 3 69 From NCERT 4

Q11 From NCERT If I be the current limit of a fuse wire of length I and radius r then select the appropriate relation 1 Ial 2 I a r 3 I a 1 4 I a r

4 A drunkard walking in a narrowlane takes 5 steps forward and 3 steps backward each step of 1 m long per second and so on Determine how long the drunkard takes to fall in a pit 15 m away from the start

n photoelectric effect the saturation photocurrent Depends both on intensity and frequency of the incident light Increase with increase in frequency of incident light Decreases with increase in frequency of incident light Does not depend on the frequency of incident light but depends on the intensity of incident light

A gas undergoes following process Ab Compressed to half of the initial volume P x V Bc CD No Isothermal expansion to intial volume Adiabatic process such that PD PA Select incorrect statemen Net heat is released AUAB 0 AUCD 0

An isolated system is one in which Mass does not cross boundaries of the system though energy may do so Neither mass nor energy crosses the boundaries of the system Both energy and mass cross the boundaries of the system Mass crosses the boundary but not the energy

7 Two thin circular discs of mass m and 4m having radii of a and 2a respectively are rigidly fixed by a massless rigid rod of length 1 24 a through their centers This assembly is laid on a firm and flat surface and set rolling without slipping on the surface so that the angular speed about the axis of the rod is The angular momentum of the entire assembly about the point O is L see the figure Which of the following statement s is are true ee dvanced 016 m 4m A The center of mass of the assembly rotates about the z axis with an angular speed of w 5 B The magnitude of angular momentum of center of mass of the assembly about the point O is 81 ma a C The magnitude of angular momentum of the assembly about its center of mass is 17 ma 2

usceptibility is positive and large for a a paramagnetic substance b ferromagnetic substance substance c non magnetic d diamagnetic substance A compass needle which is allowed to move in a horizontal plane is taken to a geomagnetic pole It a stay in North South direction only b stay in East West direction only c become rigid showing no movement d stay in any position

39 A plane wavefront 6 x 10 7 m falls on a slit 0 4 m wide A convex lens of focal length 0 8 m placed behind the slit focuses the light on a screen What is the linear diameter of second maximum a 6 mm c 3 mm b 12 mm d 9 mm

Q14 The sensitivity of a potentiometer can be increased by 1 increasing the potential gradient 2 decreasing the length of potentiometer wire 3 decreasing the current in the potentiometer wire 4 all of these 1 2 3 4

For given PV diagram AB is isothermal at T temperature CD is also isothermal at T temperature given that T T2 Then which one of the following is correct P 5Po Po I D T Vo 2Vo T B C 4vo 5vo

If the light of wavelength is incident on metal surface the ejected fastest electron has speed v If 3 the wavelength is changed to the speed of the 4 fastest emitted electron will be 1 Smaller than 3 2v 4 3 2 Greater than 4 Zero 4 3

3 86 A block of mass mis attached with a massless spring of force constant The block is placed over a rough inclined surface for which the coefficient of friction is The minimum value of M required to move the block up the plane is Neglect mass of string and pulley and fnction in pulley A B 45 a Firars exes

For CORRECT answer you will be awarded 4 Marks and for WRONG answer there is a negative marking of 1 Mark No ma Locate the position of the point P as seen by the eye in the figure below Eye 6cm 1 4 cm above P 2 10 cm above P 3 15 cm above P 4 5 cm above p 30 cm 20 cm 20 cm P 5cm 4cm p 4

The correct sequence of the increasing wavelength of the given radiation sources is a radioactive sources X rays tube crystal oscillator sodium vapour lamp aves b radioactive source X rays tube sodium vapour lamp crystal oscillator c X ray tube radioactive source crystal oscillator sodium vapour lamp d X rays tube crystal oscillator radioactive omn

Water flows along a horizontal pipe whose or section is not constant The pressure is 1 cm of where the velocity is 35 omis At a point where velocity is 65 cm sec The pressure will be 6 0 89 cm of Hg

You are given two converging lenses of focal lengths 1 25 cm and 5 cm to design a compound microscope If it is desired to have a magnification of 30 find out the separation between the objective and the eyepiece 2

A ball is thrown in vertically upwards direction with velocity 50 m s Maximum height covered by the ball will be g 10 m s

We wish to see inside an atom Assuming the atom to have a diameter of 100 pm this means that one must be able to resolve a width of say 10 pm If an electron microscope is used the minimum electron energy required is about 1 1 5 keV 3 150 keV 2 15 keV 4 1 5 MeV

Q10 For the circuit shown in the figure the value of R must be R www 1A 1 30 2 4 3 5 4 6 1 40 R 2 1A 12V 49 3 12V 352 4

103 In the figure shown one of the curves is for adiabatic process and one the curves is for isothermal process The most probable curve for adiabatic process is given by the curve PECAB A AB C EF B CD D All of them

Potential energy curve Sinusoidal is shown graphically for a particle The potential energy does not depend on y and z coordinates The maximum value of corresponding conservative force in magnitude for range 0 x 2 is n in Newton Find the value of n Take f 3 14 21 THE NALL GROUP 13 2 2 x meter AU Joule

Question For a simple harmonic oscillator of mass m 10 kg and amplitude A 2 m the variation of potential energy U as a function of displacement x from mean po sition is as shown The time period of oscillat

Seven homogeneous bricks each of length L are arranged as shown in figure Each brick is displaced with respect to the on in contact by L 10 Find the x coordinate of the centre of mass relative of the origin shown

A uniform rod of length and mass m is free to rotate in a vertical plane about a wedge A The roc initially in horizontal position is released The initia torque acting on the rod with respect to wedge is l 3l 44 A

D ALLEN Two coils A and B having turns 300 and 600 39 respectively are placed near each other On passing a current of 3 0 ampere in A the flux linked with A is 1 2 x 10 Wb and with B it is 9 0x 10 Wb The mutual inductance of the system is 1 4 10 H 2 3 x 10 H 3 2 10 H 4 1 8 102 H atquefi A i B 300 x 600 3 0 1 2 10 B 9 0 10 Pa 2 1 4 x 10 H 2 3 x 10 H 3 2 10 H 4 1 8 x 10 H A

39 A 100 Hz sinusoidal wave is travelling in the positive x direction along a string with a linear mass density of 3 5 x 10 3 kgm 1 and a tension of 35 N At time t 0 the point x 0 has zero displacement and the slope of the string is n 20 Then select the wrong alternative a Velocity of wave is 100 m s b Angular velocity is 200m rad s c Amplitude of wave is 0 025 m d None of the above

B C J May be used as a rectifier because it offers a relatively low resistance for a forward bias and very high resistance for a reverse bias May be used as a rectifier because it offers a relatively high resistance for a forward bias and very low resistance for a reverse bias Cannot be used as rectifier May be used as a rectifion

Locate the position of the point P as seen by the eye in the figure below O4 cm above P 10 cm above P 30 cm 20 cm 20 cm Scm H em 6cm 2 Eye 4 54

Q20 Current I as shown in the circuit will be 1 10 A 2 20 A 3 3 A 4 20130 A 692 wwwww 392 69 69 wwwww 10 V 66 From NCERT

Q17 The drift velocity of free electrons in a conductor is v when a current i is flowing in it If both the radius and current are doubled then drift velocity will be 1 V 2 3 V 4 4 F 4

RAI n angle 90 the resultant is 2k 1 p Q Prove that tan 0 b k k 1 bos 2 The resultant of the two vectors P and 2P is inclined at an angle with the larger one Show that c k 1 k 1 d k k 1 3 a 4 b 3 d 2 3245 c a k 1 k 1 b c 6 2 6i 2k

Q19 The equivalent resistance between A and B is Be 1 30 2 6 3 9 4 120 992 992 392 A 99 99 74 From NCERT

94 A cubical container was initially full with a lic container is now accelerated horizonta acceleration a such that one third of the spilled out Find the value of a 1 g 2 g 3 1 3 2g 3 4 g 2 fficient length is dip

single layer conducting coil is wound with no gap between adjacent urns on a cylindrical frame of radius R Diameter of cross section of the vire used is d d R If breaking stress of the material of the wire is b at what magnitude of current will the coil rupture