Physics Questions

A cell is connected between the points A and Cof a circular conductor ABCD of same material with centre at O If B and B are the magnitude of magnetic field at O due to current in ABC and ADC respectively then ratio is B B B 05 6 O 2 60 D YC

Q Assertion A For charges to be in equilibrium sum of the forces on a charge due to rest of the two charges must be zero Reason R The resultant force on a charge can be calculated using superposition principle

9 Calculate the sensible heat stored per unit volume for the following heat energy mediums when their temperature is increased by 10 C a for water p 1000 Kg m Cp 4186 J Kg C b for methyl alcohol ps 810 Kg m Cp 2512 J Kg C

A body runs on a circular path of radius R 28m with a constant speed u 4 m s Another boy starts from the center of the path to catch the first boy The second boy always remains on the radius connecting the center of the circle and the first boy and maintains the magnitude of his velocity V 4 m s If the time of chase is x sec then mark x YOUR ANSWER 44

A square shaped coil of N turns and side a is rotating with angular velocity w about an axis passing through its centre and perpendicular to its plane A uniform magnetic field of magnitude B exists parallel to the axis of rotation The maximum emf developed in the coil will be O Na Bw O O Na Bo 2 Na Bo 4 O Zero

A rod AB slides on V shaped wire with speed vin magnetic field B such that at an instant OA OB 1 If the induced emf in the loop OAB at this instant is given by Bvl then find the value of n 90 8 B V

Which of the following situations is possible a An object can have acceleration but constant velocity b The velocity of an object may be zero but acceleration is not zero c Distance and the magnitude of displacement are equal in circular motion d Average speed and the magnitude of average velocity are always equal in circular motion

A loudspeakersystem uses alternating current to amplify sound of certain frequencies It consists of two speakers in parallel Tweeter which has a smaller diameter produces high frequency sound Woofer which has larger diameter produces low frequency sound For purpose of circuit analysis we can take both speakers to be of equal resistance R The equivalent circuit is shown in the figure Select the correct alternative B R www R www mmmmm e e sin oot o The speaker connected with the capacitor acts as woofer The speaker connected with the Inductor acts YOU MARKED X

A wooden block of mass m resting on a rough horizontal table coefficient of friction u is pulled by a force F as shown in figure The acceleration of the block moving horizontally is Fcose sing M

In the circuit shown in figure below the cells and E have e m f 4 V and 8 V and internal resistance 0 5 ohm and 1 0 ohm respectively Then potential difference across cell E and E will be E 8 V 0 592 www 4 V www 4 592 30 ww 622 3 75 V 7 5 V O 4 25 V 7 5 V 4 25 V 4 25 V 5 0 V 7 0 V 19 WWW

A body moves in a circular path of the radius R with deceleration so that at any moment of time its tangential and normal acceleration are equal in magnitude At the initial moment t 0 the velocity of the body is vo then the velocity of the body after it has moved S at any time will be A B D 2S V Voe R V Voe V Voe V Voe SR 2SR

The antenna current of an AM transmitter is 8 A when only the carrier is sent but it increases to 8 93 A when the carrier is modulated by a single sine wave Find the percentage modulation A B 60 1 D 70 1 C 80 1 50 1

Three rods of the same length and the same area of the cross section are joined The temperature of two ends one T and T as shown in the figure T K T Temperature As we move along the rod the variation of temperature are as shown in the following Rods are insulated from the surrounding except at the faces B T 30 K2 04 4 4 K 3 3 L Length 45 K3 1 K K2 K3 4 4 8 0 1 K K K 3 4 K3 3 1 K 2L 60 K 3L T

Magnetic flux linked with a stationary loop of resistance R varies with time t as at T t Amount of heat generated in loop during time interval Tis aT O at 3R O a T 3R O O a T R a T 3R

A particle of mass 2m is projected at an angle of 45 with horizontal with a velocity of 20 2 m s After 1 s explosion takes place and the particle is broken into two equal pieces As a result of the explosion one part comes to rest The maximum height attained by the other part is Take g 10 m s 2 A 35 m B C D 40 m 15 m 20 m

What is the strength of transverse magnetic field required to bend all the photoelectrons within a circle of a radius 50 cm when light of wavelength 3800 A is incident on a barium emitter Given that work function 34 of barium is 2 5 eV h 6 63 10 J s e 1 6 10 19 C m 9 1 x 10 kg 31 A D 4 88 10 4 T 32 10 5 T 6 32 x 10 6 T 7 6 10 8 T

In the circuit shown in figure each resistance is of 7 and internal resistance of cell is 1 2 The reading of ideal ammeter A is 14 V 122 2 A 4 A 8 A 6 A www www www www A www www www

Soap solution can be spread into a fairly large vertical thin film but the same cannot be done with water Why A Density of water is more than that of soap solution B Surface tension of water is more than that of soap solution C Surface tension of water is less than that of soap solution D Because of some reason other than those

The diagrams below show regions of equipotentials 20V 40V 20V 40V 10V 30V HUD B A B A B A 10V 30V a 10V 30V b 20V 40V c 20V 40V 10V 30V B d A positive charge is moved from A to B in each diagram 1 In all the four cases the work done is the same 2 Minimum work is required to move q in figure a 3 Maximum work is required to move q in figure b 4 Maximum work is required to move q in figure c

According to Faraday s law of electromagnetic induction the total charge flown through a cross section of a conducting loop depends upon Initial magnetic flux only Final magnetic flux only O Rate of change of magnetic flux ONet change in magnetic flux

ven V VI I 22 Use source transformation to obtain Circuit B so that it is equivalent to Circuit A Determine V in Circuit B Circuit A Circuit B 03 V 2 3 A 1 3 V 30 30 www R V 10 2 ww Vz 10 2 V 5 A 1 R V 50 5 V Vz 50 ww Vx 29V V1 6V R1 6 ohm R2 2 5 ohm

Q16 From NCERT The photon radiated from hydrogen corresponding to the second line of Lyman series is absorbed by a hydrogen like atom X in the second excited state As a result the hydrogen like atom X makes a transition to nth orbit Then 1 X Het n 4 2 X Litt n 6 3 X Het n 9 4 X Li n 9

F a e 2 akt k t temperature A X distance The dimensions of Bis B D Boltzmann constant MLT 4 M L 2T MLT 2 M LT 1

If the rates of cooling of two different liquids put in exactly similar calorimeters and kept in identical surroundings are the same then which among the following is most suitable option A Equal masses of the liquids at the same temperature are taken B Equal volumes of the liquids at the same temperature are taken D Both 1 and 2 Insufficient information

A sound source emitting sound of frequency 450 Hz is approaching a stationary observer with velocity 30 m s and another identical source is going away from the observer with the same velocity If the velocity of sound is 330 m s 1 then the difference of frequencies heard by observer is A B D 103 5 Hz 82 5 Hz 33 5 Hz 92 5 Hz

TYPE questions Each question has 4 choices 1 Read More A hollow charged metal sphere has radius R If the potential difference between the surface and a point at distance 3R from centre is V then the electric field intensity at a distance 5R from surface is V 6R V 12R V 24R

A cylinder of mass M length L and radius R has two cords wound around it with their ends attached to the ceiling as shown in the figure The cylinder is held horizontally with the two cords vertical When the system is released from rest the linear acceleration of the cylinder as it falls will be R A O 93 2g 3 3g 2

A stationary light smooth pulley can rotate about a fixed horizontal axis A light rope passes over the pulley One end of the rope suppors a ladder with a man and other end supports counter weight of mass M Mass of the man is m Initially the system is stationary and the centre of mass of the counter weight is at a height h from that of the man as shown in the figure If the man starts to climb up slowly such that his center of mass reaches at the level with that of the counter weight A A Distance moved by counter weight relative to ground is w te ros B Distance moved by counter weight relative to ground is mh M m Mh M m C Distance moved by man relative to ladder is 00 D Distance moved by man relative to ladder is mh 2 M m mh M m M

27 If the radius of the Al nucleus is estimated to be 13 3 6 Fermi then the radius of 125 Te nucleus be nearly A B 6 Fermi D 8 Fermi C 4 Fermi 5 Fermi

That when the elctrons release potential energy what actually happens is that they come to a low energy state and come close to the nucleus which directly affects the attractive force btw nucleus and electron and which is the cause for kinetic energy

2 25 1 Four holes of radius R are cut from a thin square plate of side 4R and mass M The moment of inertia of the remaining portion about z axis is 3 M MR 12 89 X 2 8 10T 3 16 MR2 2 2 4 g sing 3 E 4 4 3 6 MR MR

4 j nqva in the direction of current flow A non conducting ring of radius R has two positive point charges lying diametrically opposite to each other each of magnitude Q The ring rotates with an angular velocity oo If I is the equivalent current then 1 IQoo Qo 200 T 2 I 41 de daar i 1 I Qo 3 in our faufta fergan va s af finn 0 Qu 2000 H 2 1 3 4 1 3

A particle of mass 2 kg is moving in XY plane in a circular path of radius 3m with constant angular speed 5rad s The motion of the particle is being observed from a car moving with acceleration d 31 4k m s Then the D None of these magnitude of centrifugal force F acting on the particle is A 150N B 0 F 10N C 0 F 6N A block is at rest on a rough inclined plane

37 A bubble is at the bottom of the lake of depth h A the bubble comes to sea level its radius increase to three times If atmospheric pressure is equal 1 metre of water column then h is equal to HT 261 2 1 3 251 4 301

3 How many seconds are there in a leap year Express it in standard form 4 If the velocity of light is 3 0 108 metres per second calculate the distance travelled by light in a light year and express it in standard form Hint One light year Distance travelled by light in a year

Two identical balls A and B each of mass 0 1 kg are attached to two identical massless springs The spring mass system is constrained to move inside a rigid smooth pipe bent in the form of a circle as shown in the figure The pipe is fixed in a horizontal plane The centres of the balls can move in a circle of radius 0 06 m Each spring has a natural length of 0 067 m and spring constant 0 1 N m Initially both the balls are displaced by an angle rad with respect to the diameter PQ of the circle as shown in the figure and released from rest The frequency of oscillation of balls is P A 1 B 2 1555 3 A Am eeeee Hz Hz Hz 100000 Hz TT 6 oooooo 0 06 m TT 6 B 100000 hell e o o o ele e e

Boyle s law states that the volume of a gas is inversely proportional to the pressure if the temperature is held constant A gas has a volume of 170 6 mL when the pressure is 1 31 atm What is the volume in mL to one decimal place if the temperature remains constant and the pressure is increased to 5 96 atm Your Answer

dt SolveLancer Test In the given figure a ring of radius r mass m is uniformly charged and has total charge Q The ring is free to rotate in the plane Magnetic field is turned on at t 0 and changes at rate 48 A charge Q is placed at center C of the ring Find the time when tension in ring is instantaneously zero Test k SolveLancer b c km km KmQ Br 0 B

Three objects A B and C are kept in a straight line on a frictionless horizontal surface They have masses m 2 m and m respectively The object A moves towards B with a speed 9 m s and makes an elastic collision with it Thereafter B makes pefectly inelastic collision with C All motion occur on same straight line The final speed of the object C is m A 1 3 m s 3 5 m s 2m B m C 2 4 m s 4 1 m s

4 Intensity of bulb A remains same and intensity of bulb B decreases 0 A conductor of area of cross section A having 40 charge carriers each having a charge q is subjected to a potential V The number density of charge carriers in the conductor is n and the charge carriers are moving with average velocity V A current I flows in the conductor If is the current density then 1 nqV in the direction of current flow to 4 Al 3417 Ted vai a i 1 3 jnqV in the direction perpendio questionpape nqV 2 nqv in the direction opposite to current t current flow 4 jnqv in the direction of current flow I wanted t n E 4 nov f a V faya y er 2 ve fayda a fen 3 Va 9

18 In the circuit shown the value of of the transistor is 48 If the base current supplied is 200 A what is the voltage at the terminal Y a 0 2 V b 0 5 V c 4 V d 4 8 V Vcc 5V gy 500 S IB 200 A Y 2020

A block of mass m is released from height h from a fixed smooth inclined plane At the foot plank of mass m is kept on smooth surface Friction coefficient between plank and block is and block just fails to leave the plank of length C Pick the correct options for the work done by friction on the block and the plank mgh A 4 mgh 2 3mgh 4 mgh B C D m m

A body is projected at 30 with velocity v from point A on the ground At the same time another body is projected vertically upwards from B with velocity v2 from the ground The point B lies vertically below the highest point of the trajectory of ball A For both the bodies to collide what should be the ratio of 1 V2 A 1 B 2 C N N D 2

A particle strikes smooth floor with speed 20m s as shown in figure After the collision it performs a projectile motion having range 15m The coefficient of restitution for the collision is g 10 m s 20m s R 15m

The value of steady current in 2 resistance shown in figure is 2 F HH 3 0 A O 1 2 A 202 www 0 9 A 392 www 492 www 6 0 V 2 892 www

The equivalent resistance between points A and D of the combination of resistances shown in figure is 10 Q 1092 www A C 10 Q2 W 2092 B WWW 10 92 30 2 352 20 22 Read More www ww 1092 20 22 www 1092 D

The figure shows currents in a part of electrical circuit then current is 2 A 2 A O 1 7 A 1 7 A Read More O 2 3 A 1 A 1 3 A

Six identical capacitors each of capacitance C are connected as shown The equivalent capacitance between points A and Bis A WIN 314 00 0 0 Read More 2C E B

Figure shows a balanced wheatstone bridge The value of Ris 100 Q A ww 200 2 20 22 25 22 40 22 15 22 100 2 D E www 40 Q2

26 NTA Test 23 Single Choice md The main scale of a vernier calliper reads 10 mm in 10 divisions 10 divisions of vernier scale coincide with 9 divisions of the main scale W he two jaws of the callipers touch each other the fifth division of the vernier coincides with a main scale division and the zero of the vernier he right of zero of the main scale When a cylinder is tightly placed between the two jaws the zero of vernier scale lies slightly to the left of 2 cm and the fourth vernier division coincides with a main scale division The diameter of the cylinder is thon to