Basic Physics Questions and Answers

c 7 d None of these 1 Two coaxial solenoids of different radii carry current I in the same direction Let F be the magnetic force on the inner solenoid due to the outer one and F be the magnetic force the outer solenoid due to the inner one Then JEE Main 2015 a F F 0 b F is radially inwards and F is radially outwards c F is radially inwards and F 0 D d F is radially outwards and F 0 on separated i and it other it in a The b The c The d The con 13 The ma cm fro of ind would

From a point at a height h above the ground a particle A is projected with a velocity v in an upward direction making an angle with the horizontal Another particle Bis projected from the same point with the same velocity v but in a direction diretly opposite to A The two particles hit the ground at a distance apart sisalim 05 v baage leb eig erti of ludibreqpaq yol nhi a 31 2v g 2v ei sis0 evode 0 cos v sin 0 2gh B sin v sin 0 2gh V h A be oni ne qu batejong R R nanogmoo e 70E noiteniboni 2v 2 4 g balbajor cos v sin 0 2gh 2v cos v cos 2gh

2 You are given mn wires of equal resistance If mi wires are in series and n such combinations are in parallel the resultant resistance is R If n wires are in series and m such combinations are in parallel the R R resultant resistance is R Then is 1 1 1 2 m n 3 m n 4 n m

Power supplied to a particle of mass 2 kg varie with time as p 31 watt Here tis in seconds If velocity of particle at t 0 is v 0 then velocity of particle at t 2 will be 1 ms 1 2 ms 1 4 ms 1 6ms 1

At room temperature number of electrons in a pure Ge crystal is 1015 m 3 If 1021 Ga atoms are mixed per m in the crystal then the number of electrons in the extrinsic semiconductor is Question Type Single Correct Type 1 1021m 3 2 1015m 3 3 10 m 3 106 m 3

An equiconvex lens has an aperture of diameter 6 cm At the centre its thickness is 0 2 cm If it is made of material of refractive index 1 6 what is its focal length 11 6 cm 24 5 cm 37 5 cm 19 5 cm

A helicopter is trying to land on a submarine deck which is moving south at 17 m s relative to water Wind is blowing at 12 m s relative to water in west direction If to the submarine crew the helicopter is descending vertically at 5 m s what is its speed relative to the air assuming sea water to be still as shown in figure If your answer is v v v k in m s vx v v fill the value of 17 Z N Z k D A Y

Gateway to AllMS at a distance 2d apart rents flowing out of the n Magnetic field along magnetic field for points ted in 1 Steway to AllMS A long straight wire carries current i along negative z axis The magnetic field at the point x y 0 is 1 3 Hoi yi xj 2 X x y Hoxj yi y 27 x y 2 4 i x Ho xi yj 2x x y Moi Ho xi yj y 2 x y 23 Find the magnetic field at the centre of the circular carc of radius r as shown 26 Moving Chair Cross sectional view of A current i uniform cross section is flowin cylinder of radius R

A closed tank containing water is moving in a horizontal direction along a straight line at a constant speed The tank also contains a steel ball and a bubble of air If the tank is decelerated horizontally then i the ball will move to the front ii the bubble will move to the front iii the ball will move to the rear iv the bubble will move to the rear Find out which of the above statements are correct a i and ii b i and iv c ii and iii d iii and iv

S A reference frame S is moving with a constant relativistic speed with respect to another stationary reference frame S If path of particle in S frame is circle then in frame S it will appears as 1 straight line 2 circle 3 parabola 4 ellipse 18 0 1 28 07

A hollow cylinder of 4R is rotating about fixed horizontal axis passing through point 0 with angular velocity A solid cylinder of radius R is rolling without slipping with respect to inner surface of hollow cylinder At the given instant the line OC has angular velocity of 20 Point A and B are topmost

Q2 iv If one penetrates a uniformly charged spherical cloud electric field strength a decreases directly as the distance from the centre b increases directly as the distance from the centre c remains constant d None of these

A small solid ball of density p is held inside at point A of cubical container of side L filled with an ideal liquid of density 4p as shown in the figure Now if the container starts moving with constant acceleration a horizontally and the ball is released from point A simultaneously then O For ball to hit the top of container at end Q a 3g 0 For ball to hit the top of container at end Q a 2g Ball hits the top of container at end Q after a time t Ball hits the top of container at end Q after a time t L 3g 2L 3g L 2 P AXO L 2 R L Q a As

A batch of one hundred bulbs is inspected by testing four randomly chosen bulbs The batch is rejected if even one of the bulbs is defective A batch typically has five defective bulbs The probability that the current batch is accepted is

Two particle A and B are projected at t 0 as shown in figure At any time t both collide in air then find value of t 60 m s 50 m s A B C D A 30 10 3 3 4 5 3 4 20 3 3 4 2 3 3 4 200 m a B

3 In a certain region of space there exists a uniform electric field of strength E along x axis and uniform constant magnetic field of strength B along z axis A particle of charge q and mass m is projected with speed v parallel to x axis from a point a b o When the particle reaches a point 2a 2 0 its speed becomes 2v then E 1 E 3 E 3 my 2 qa 2mv qBa 2 E mv qB 3 4 E vB 2

36 A wire of 1m long has an area of cross section of 2 x 10 cm and has a resistance of 10ohm The resistivity of the material of the wire is 1 2 x 10 6 cm 2 2 x 100 cm 3 2 x 10 22 cm 4 2 x 10 cm

Question Calculate The Standard Reaction Entropy At 298 K Of The Following Reactions A 2 Calculate the standard reaction entropy at 298 K of the following reactions a 2 CH3CHO g O2 g 2 CH3COOH 1 J K 1 mol 1 b 2 AgCl s Br2 I 2 AgBr s Cl2 g J K 1 mol 1 c Hg l Cl2 g HgCl2 s J K 1 mol 1

3 As one moves along the line of stability from 56Fe to 235 nucleus the nuclear binding energy per nucleon decreases from about 8 8 MeV to 7 6 MeV This trend is mainly due to the 1 Short range nature of nuclear forces 2 Tensor nature of nuclear forces 3 Spin dependence dependence of the nuclear forces 4 Long range nature of coulomb forces

This section contains 35 SINGLE CORRECT TYPF questions Fach question has 4 Read More A charge 8 85 C is placed at the centre of a cube The electric flux in Sl units through any one face will be O 106 6 O 1012 6 O 10 13

TYPF questions Out of these 15 questions Read More Three capacitors with capacitance equal to 6 F 6 F and 3 F respectively are connected in series with 20 volt line Find the charge on 3 F 6 F 6 F 3 F HHH 20 V 20 C 30 C 40 C

A uniformly thick plate in the shape of an arrowhead has dimensions as shown The centre of mass lies at a point approximately A 1 5 cm to the right of O B 3 cm to the right of O C O itself D 1 67 cm to the right of O Space for Rough work 6 cm Mem

22 ALLEN If a solid sphere is rolling the ratio of its rotational 22 energy to the total kinetic energy is given by 1 7 10 2 2 5 3 10 7 4 2 7 de at du m i qui 1 7 10 3 10 7 2 2 5 4 2 7 Ch

Figure shows small part of circuit Given C C2 C3 C4 5 F Which of the following statement is are true B 10V O Potential of point O can be determined but that of B can t be determined 0 Potential of both point O B can t be determined C 0 C C C R www L 10V If charge on capacitor C were also specified potential of point O can be determined but that of B cann t be determined If charge on capacitor C were also specified potential of both the point O B can be determined

In an experiment to measure the diameter of a wire using a screw gauge of resolution 0 001 cm which of the following may correctly represent the measurement 1 01 235 cm 2 01 2351 cm 3 01 24 cm 4 01 23500 cm

A coaxial cable having radii a b and c carries equal and opposite currents of magnitude i in the inner and outer conductiors What is the magnitude of the magnetic induction at point P outside of the cable at a distance r from the axis b N

A light beam of power P consists only of wavelength A If Plancks constant is h and the speed of light is c then the number of photon emitted per second in the beam is O h Pi hc Pi

2 Activity when measured as counts per minute is mixture of two isotopes A Difference between the activities of the two isotopes B Sum of the activity of each isotope C Product of activities contributed by each isotope D Ratio of activities of one isotope to the other in case

Three forces of magnitudes 2 N 3 N and 6 N act at corners of a cube along three sides as shown in figure Find the resultant of these forces is N 43N 0 6N 2N

The horizontal component of force on a curved surface is equal to the a product of pressure intensity at its centroid and area b c weight of liquid vertically above the curved surface d force on a vertical projection of the curved surface force on the horizontal projection of the curved surface

52 The reverse saturation current at 300 K of a p n junction Ge diode is 5 A The voltage to be applied across the junction to obtain a forward current of 50 mA will be approximately 1 0 012 V 3 0 476 V 2 0 238 V 4 1 2 V

ree point masses are placed at the corners of a triangle as shown in the figure below Find the center of mass of the three mass system using the 60 g mass as the origin Positive x the right and positive y is up 60 g 4 cm 3 cm 150 g

The magnitude of radius vector of a point varies with time as r Bt 1 at where a and Bar positive constant The distance travelled by this body over a closed path must be B B B 2 2 B A C a D

3 65 4 67 A current I 10 sin 100 t A is passed in first 13 coil which induces a maximum e m f of 5n volt in second coil The mutual inductance between the coils is 1 10 MH 3 25 mH 2 15 mH 4 5 mH 3 65 4 67 RT I 10 sin 100 t A dat fedi gus voltad 34 fayda Ste atli 1 10 MH 3 25 mH 2 15 mH 4 5 mH

Solve the following numerical 2 X 3 6 1 A container filled with 50 cm of milk weighs 80g The container alone weighs 34g Find the density of the milk 2 A body of mass 5 kg is moving with the velocity 6m s Calculate the kinetic energy of the body 3 Calculate the time taken by an aircraft to cover the distance of 2100 km with an PDF Anti Copy for Android Update to Pro to remove watermark average velocity of 900 km hr calculate the time in mixed fraction

A very broad elevator is going up vertically with a 18 constant acceleration of 2ms At the instant when its velocity is 4 ms a ball is projected from the floor of the elevator with a speed of 4 ms with respect to the elevator at an angle of 30 The time taken by the ball to return the floor is g 10 ms e 3 s 4 Is gast farve fare m s 4 m s fat m s 30 at an g 10 ms e N 14 3 2 s 4 Is art

The vector sum of two forces is perpendicular to their vector difference In that case the force 1 Are equal to each other 2 Are equal to each other in magnitude 3 Are not equal to each other in magnitude 4 Cannot be predicted

3 1 0 KQ 4 None of these D A force F acting on an object varies with distance 30 x as shown here The force is in N and x in m The work done by the force in moving the object from x 0 to x 6 is F N 3 2 I 0 1 18 0 J 3 9 0 J 1 2 3 4 5 6 7 x m 2 13 5 J 4 4 5 J 3 1 0 KQ faf x 0 1 x 6 a fare F N 3 2 1 4 0 1 18 0 J 3 9 0 J 1 2 3 4 5 6 7 x m 2 13 5 J 4 4 5 J

An open cubical tank of 2 m side is filled with water If the tank is rotated with an acceleration such that half of the water spills out then the acceleration is equal to a g 3 b g 2 c 2g 3

20 Magnetic field Bo exists perpendicular inwards The resistance of the loop is R When the switch is made closed the current induced in the circuit 1 3 A Botv F 2B v R K X N AS Medical X 38 v 4 Zero

A particle is moving in a circle of radius 2m with angular velocity 2t 4t where t is time in sec and is in rad s A Angular acceleration of the particle at t 2 sec is 4 rad s B Angular acceleration of the particle at t 2 sec is 8 m s C Angular acceleration of the particle is constant 32 D Angle rotated by particle in time interval t 0 to t 4 sec is radian

A particle moves in rectilinear motion Given the a s curve shown in figure Initial velocity of the particle is 10m s Velocity of the particle after the particle has traveled 30m is X m s The value of X 10 is a m s 10 15 30 s m

Two organ pipes are identical except that one is filled with oxygen and other with a mixture of oxgen and nitrogen The temperature and total pressure in each pipe are the same when two are sounded together a note of 440Hz is heard which beats one every second What is the percentage partial pressure of the nitrogen in the mixture Assume that the molecular weight of oxygen is 32 and of nitrogen 28 and their principal specific heats are identical

4 None of these 4 44 24 1 H61 0 A circular disc of radius R is removed from a 20 Ref 2R fact fo bigger circular disc of radius 2R such that the circumferences of the discs coincide The centre of mass of the new disc is aR from the centre of the bigger disc The value of a is 1 1 1 3 2 1 2 3 1 6 4 1 4 The maximum force in addition to the 21 f 1 1 3 2 1 2 3 1 6 20 C

ALLEN vibration 12 The magnetic needle of a magnetometer makes 12 oscillations per minute in the horizontal component of Earth s magnetic field When an external short bar magnet is placed at some distance along the axis of the needle in the same line it makes 15 oscillations per minute If the poles of the bar magnet are interchanged the number of oscillations it makes per minute is 1 6T 2 63 3 65 4 67 A current I 10 sin 100m t A is passed in first 13 a 12 f fe 15 and at af ad fanm at ge fer fand acr 1 6T 3 65 I 2 63 4 67 10 sin 100m t Aug

A 1 kg block is being pushed against a wall by a force F 75 N as shown in the Figure The coefficient of friction is 0 8 The magnitude of acceleration of the block is A 10 m s B 0 m s F 37 C 5 m s D None of these

4 n 4 A solid sphere of mass 10 kg is placed on a 9 rough surface having coefficient of friction 0 1 A constant force F 7 N is applied along a line passing through the centre of the sphere as shown in the figure The value of frictional force on the sphere is F 7N 1 IN 3 3 N 0 1 2 2 N 4 7 N st Leader Achiever Course ALL PHASE 3 n 3 100 4 n 4 is a m farger 7 F 8 at 1 IN 3 3 N F 7N 0 1 2 2N 4 7 N 1001CMD303119110

system of two concentric uniformly charge conducting shells having charges of Q and Q ar shown in the figure The shells are having radius o R and R respectively The thickness of outer shell is t and we can assume that the thickness is negligible compared to other dimensions of the charged system so that the shell can be treated as thin shell What will be the electrostatic stress developed in the outer charged conducting shell A C 3Q Q Q 2Q Q 64m R t 187 P 2 O D R2 R B Q 2Q Q 32 Rit OYN

Consider the following statements for lead storage a It consists of a grid of lead packed with PbO2 as anode and a lead cathode b 38 solution of H SO4 is used as an electrolyte c It is commonly used in automobiles and invertors Which of the above statements are correct a and c Ob and c a and b a b and c

A ball is projected with a velocity v making an angle 8 with the horizontal The position co ordinates of a point on its trajectory are given by x 3t m and y 4t 5t m What is the velocity of projection O 5 m s O O 6 m s 8 m s