Basic Physics Questions and Answers

4 70 The time period of a bar magnet oscillating in a uniform magnetic field is 3 seconds if the magnet is cut into two equal parts along the equatorial line of the magnet and one part is made to vibrate in the same field what is the time period Ans T 2 I MH

A vessel has 10 g of hydrogen gas at pressure P and temperature 400 K A small hole is made in it so that hydrogen leaks out How much hydrogen leaks out if the fina 3 pressure becomes half and temperature becomes th of its previous value O 1 g 10 g 4

It is necessary to illuminate the bottom of a well by reflected solar beam when the light is incident at an angle a 40 to the vertical At what angle to the horizontal should a plane mirror be placed a 70 b 20 c 50 d 40

A block of mass 10 kg is kept on an inclined plane of inclination 30 and friction coefficient between the block and inclined plane is 1 fl 7 3 Find the minimum value of force in newton required to move the block up the inclined plane Take V 3 1 732 g 10 m s 10 kg 1 3 Ta 30

Q6 A 800 N man starts climbing a ladder that placed against a wall as shown in given figure Neglecting the weight of the ladder determine how far up the ladder the man can climb before the ladder starts slipping Assume coefficient of static friction between the surfaces as 0 25 8m 30

A projectile 61 8 m s is projected with initial velocity from the ground The velocity when it is about to hit the ground is assuming y axis is along vertical direction NCERT Pg 78 1 67 81 m s 3 61 81 m s 2 61 8 m s 4 61 8 m s

Position of a particle varies with time t in s asr 21i 3 m The magnitude of acceleration of particle is OPTIONS MARK FOR REVIEW CLEAR SELECTION OA 2 m s OB 4 m s C 5 m s

26 Three charged particles having charges q 2q and q are placed at points a 0 0 0 and a 0 respectively The expression for electric potenital at 0 r is 1 3 K k kqa r4 4kqa 2 1 4T EO r a 2 4 kqa 8kqa

26 A 800 N man starts climbing a ladder that placed against a wall as shown in given figure Neglecting the weight of the ladder determine how far up the ladder the man can climb before the ladder starts slipping Assume coefficient of static friction between the surfaces as 0 25 8 m 30

Attempt All 35 questions A particle of mass m is attached at one end of a mass less rod and whirled round a verticle circle To complete the circular path the minimum speed given to the particle from lowest pos 5g 0 m

ithout lated on of our pop current flows in a ving of isosceles trapezium The ratio of the bases of the trapezium is 2 Find the magnetic induction B at symmeric point O in the plane of the trapexium The length of the smaller base of the trapexium is 100mm and the distance r 50mm B da 4 61 do di NQ Figure 4 264

Microscope is an optical instrument which 1 Enlarges the object 2 Increases the visual angle formed by the object at the eye 3 Decreases the visual angle formed by the object at the eye 4 Brings the object nearer

The spring balance A reads 2 kg with a block m suspended from it A balance B reads 5 kg when a beaker filled with liquid is put on the pan of the balance The two balances are now so arranged that the hanging mass is inside the liquid as shown in figure In this situation a The balance A will read more than 2 kg b The balance B will read more than 5 kg c The balance A will read less than 2 kg and B will read more than 5 kg d The balances A and B will read 2 kg and 5 kg respectively 1 2 Question Type Single Correct Type 3 4 a a and b b and c 00000 a b and c A B

Consider the circuit shown in figure The switch S is closed for t 0 and steady state conditions are established The switch is then opened at t 0 Then choose the CORRECT option s for the instant immediately after t 0 A Current through R is 3V 8R R R www L R 2R S at t 0 C Potential difference across L is V R R www R 2R www L www www R 2R B Current through R is V 8R 3V D Potential difference across L is 2

terminal C A battery always delivers energy to the circuit D None of these Mark the correct statement s related to a real battery connected in an electrical network A There is always a voltage gain across the battery B There is always a voltage drop across the battery C There is either a voltage drop or gain across a battery D None of these onnected in parallel then the equivalent resistance of the

26 A person is running along a circular track of area 625 m with a constant speed Find the distance traveled and displacement in 30 s and 15 s respectively if he has to complete the race in 30 s

NEET AIIM 130 Semiconductor Electronics Materials Devices and Simple Circuits Example 5 The diode used in the circuit shown in the figure has a constant voltage drop of 0 5 V at al currents and a maximum power rating of 100 mW What should be the value of the resistor R connected in series with the diode for obtaining maximum current put less I Solution O 0 2A And resistance R Current through diode or circuit 100 10 W 0 5V ww R Net voltage Current 1 5 V Power Voltage

3 21 8 4 11 07 On passing 1 8 L of oxygen through ozonizer gives 1 6 L of a mixture of ozone and oxygen What is the mole fraction of ozone in the resultant mixture 1 0 15 3 0 40 2 0 25 4 0 50

Choose the correct statement s related to battery in an electric circuit A A battery always delivers electric current to a circuit B In a circuit current always comes out of its positive terminal and enters into its negative terminal C A battery always delivers energy to the circuit D None of these 5

with different orientations of axis 3 19 A man can swim with a speed of 5 km h in still water How long does he take to cross a river 1 0 km wide if the river is flowing steadily at 3 km h and he makes his strokes 4 normal to the river current NCERT Pg 86 1 20 min 2 30 min 3 12 min 4 15 min 20 A particle starts from origin at ith n 5 6 scalars of units NCE Displacing a vector parallel to the vector unchanged Such called ENC Multiplying a vector by a neg gives a vector whose to the direction of A N Vector addition follows law N On adding two equal and opp resultant will be a

re b 6 17 The component of 31 41 in the direction of i 1 is NCERT Pg 87 1 121 2 i 2 3 1 1 4 1 1 20 A particle starts from a velocity 4 0 m s and with a constant 61 41 m s The y coordinate of particle 1 6 s 2 4 s 3 8 s 4 5 s

In a common emitter transistor amplifier the output voltage appearing across the collector resistance of 3 kQ2 is 3 V Its current amplification factor is 100 VB 2 V and Vr 0 6 V If the dc bias current has to be 10 BB BE times the input signal current the value of R that must be in series with VBB is B A 1 4 k B 14 k C 1 422 D 142

acc tion 10 Which of the following vector operation is meaningful NCERT Pg 85 Multiplication of any two vectors 2 Adding any two vectors 3 Adding a component of vector to the same vector 4 Both 2 and 3

Three identical emf sources are attached to a single circuit element a resistor a capacitor or an inductor The current amplitude is then measured as a function of frequency Which one of the following curve corresponds to inductive circuit Options a Imax a b E d

7 Two small balls each carring a charge q are suspended by equal insulated strings of length I meter from any point This arrangement is carried in a satellite in space The tension in each string and angle between the string will be NCERT XII 1 10 1 Kq 4 2 180 q 412 3 K 90 2 K9 12 00 4 K 180

way with a speed of the market for 30 d returns to home The magnitude of urney is NCERT Pg 57 0 km h 5 km h th 300 m and allel tracks each h in the same The driver of train Q and ter 40 s the e driver of Q en the trains ERT Pg 56 16 Two stones are thrown up from the edge of a cliff 300 m high with initial speed of 10 m s 2 and 20 m s Which of the following graph best represents the variation of relative position of second stone with respect to first stone till both the stones are in air neglect air resistance g 10 m s 3 4 NCERT Pg 59 5 x x 3 X X x x t 2 4 X X a Road New Delhi 110005 Ph 011 47623456 6 7 of objects along a called rectilinear motion In NCERT Pg 39 we study ways to describe motion without going into the causes of motion NCERT Pg 39 A co ordinate system along with a clock constitutes a Displacement has both NCERT Pg 40 and NCERT Pg 40 The magnitude of displacement equal to the distance traversed by an object NCERT Pg 41 The magnitude of average velocity in general is than the average speed NCERT Pg 43 The velocity at an instant is defined as the limit of as the time interval becomes small NCERT Pg 43 8 9 For uniform m at al Acceleration 10 The area und moving objec a given time 11 The accele change val Changes are a ch 12 Free fall is th 13 The magnitude 14 On an x t a time inte 2021 09 09 00 41

heither x nor X 11 A quarter horse power motor runs at a speed a 600 rp m Assuming 40 efficiency the work don by the motor in one rotation will be NCERT XI 1 136 1 7 46 J 2 7400 J 3 7 46 ergs LAN 746

t ome 47 can not at e n 9 kn The velocity time graph of a particle moving along a fixed direction is as shown in figure The average velocity of particle between 5s to 10 s is NCERT Pg 60 12 1 15 6m s 2 6 0m s 3 8 9 m s 0 5 10 t s

3 10 m s 4 5 m s 14 If two vectors ai 61 and B bi cj are 1 CAMERA equal then correct options for value of a b and c is NCERT Pg 66 1 a b 2 a c 3 c 6 4 Both 1 and 3 17 The component of of 1 i is 2 4 IN IN j 2 1 2 1

12 Which of the following option is correct NCERT Pg 86 1 Each component of a vector is always scalar 2 Three vectors not lying in a plane can never add up to give null vector 3 Two vectors of different magnitude can be add up to give null vector 4 Minimum number of vectors to give null vector is five 3 A particle A is moving with velocity 1 15 Equation of trajectory y 3x 5x Then ang with vertical is Assume x a and y axis as vertical 1 45 2 30 3 60 4 53 16 A projectile is projected 101 20 m s from t

Dear teacher please tell me Resistivity Resistance relat ion with temperature also their graph in case of semico nductor insulator conductor in detail needed for neet 2021 will be really grateful

Please explain this question At t 0 a body is at a point whose position vector is r xi yj zk and starts with velocity V Vx vy v k If point O is at Vyj r 0 then body is always moving towards point O when a F v 0 b F V 0 c xvx yvy zv 0 d xvy yvx Zv 0 1 a and b are correct 2 b and d are correct 3 a b c are correct 4 All are correct

An iron rod of susceptibility 599 is subjected to a magnetising field of 1200 A m 1 The permeability of the material of the rod is Po 4x10 7TmA 1 2 4mx 10 7 Tm A 1 2 4mx 10 4 Tm A 1 8 0 x 10 5 T m A 1 1 2 3 4 2 4mx 10 5T m A 1 kang

One end of a spring of natural length and spring constant k is fixed at the ground and the other is fitted with a smooth ring of mass m which is allowed to slide on a horizontal rod fixed at a height figure Initially the spring makes an angle of 0 with the vertical when the system is released from rest If the speed of the ring when the spring becomes vertical is 2 3 m s then find the value of angle 0 in degree Vm kmmmmm Address Reliable Institute A 10 Road No 1 IPIA Kota 324005 Rajasthan INDIA visit us at www reliablekota com Email info reliablekota com all ver 91 744 2665544

5 A uniform rod of length L is free to rotate in vertical plane about a fixed horizontal axis through B The rod begins rotating from rest from its unstable equilibrium position When it has tuned through an angle 0 its average angular velocity is given as 1 3 6g L 6g sin 0 A 0 COS BB 2 4 A 6g 6g sin 2 cos 0

please explain the process how we have concluded the direction of induced current 19 A magnet is moved in the direction indicated by an arrow between two coils AB and CD as shown in figure The direction of induced current in the straight wire is B

Amiliammeter range 10MA r 129 Is joined in circuit The metre give full scale deflection for current I when A and B are used as its terminals i e current enters at A and leaves at B C is left isolated The value of I is a 100 mA b 900 mA c 1 A d 1 1 A 992 10 mA ww 0 19 B www 0 9 2 C 952

9 7 D A closely wound solenoid 80 cm long has 5 layers of winding of 400 turns each The diameter of solenoid is 1 8 cm If it carries current of 8 A then magnitude of magnetic field intensity inside solenoid near its centre is NCERT Pg 173 1 1 62 x 104 T 2 25 13 x 10 T 3 3 1 x 10 2 T 4 16 8 x 10 T

3 4 5 2 104T Consider a tightly wound 200 turns coil of radius 10 cm carrying current of 10 A The magnitude of magnetic field at the centre of the coil is NCERT Pg 151 2 0

please explain 40 A ray of light travelling in vacuum enters into a medium of refractive index It is found that angle of refraction is half of the angle of incidence then value of angle of incidence is cos FIN 2 cos 2 sin 2 0 Solution Answer 2 Given 1 sini usinr 2 sin cos sin

1 A force F 3i 4j N acts on a 2 kg movable object that 1 2kg 3 4 A 446 moves from an initial position d 31 21 m to final position d 5i 4j in 6s The average power delivered by the force during the interval is equal to 1 8 watt watt 3 15 watt 4 None of these and 6 surf frafa d 31 21 fufa d 51 41 facafu ft 1 82 2 500 atz 3 15 afz 4

3 ABCDE is a channel in the vertical plane part BCDE being circular with radius r A block is released from A and slides without friction and without rolling The block will complete the loop if h is 3 1 h r 3T 3 h r 2 E D D B 5 2 h 2 5 4 h r

In a conical pendulum the length of string is I and 0 is the angle of string with horizontal The time period of revolution is proportional to 1 cose 2 sine 1 cose 3 4 1 sine

19 A uniformly charged conducting sphere of 20 Incorrect statement an 3 m diameter has a surface charge density of 90 C m What is total electric flux leaving the surface of sphere 1 1 76 x 108 N m C 1 22 87 x 108 N m C 1 3 5 2 x 108 N m C 1 4 4 52 x 106 N m C 1 NCERT Pg 48 1 Gauss s law is electric field whe symmetry 2 Gaussian surfac continuous charg

A combination of two thin lenses with focal lengths f and f respectively forms an image of distant object at distance 60 cm when lenses are in contact The position of this image shifts by 30 cm towards the combination when two lenses are separated by 10 cm The corresponding values of f and f are 1 30 cm 60 cm 2 20 cm 30cm 3 15cm 20 cm 4 12 cm 15 cm

as the 4 43 A charged particle of mass m and charge q is accelerated through a potential difference of V volts It enters a region of uniform magnetic field B which is directed perpendicular to the direction of motion of the particle The particle will move on a circular path of radius A C Vm 2qB 2Vm 1 9 B B D 2Vm 9B Vm q 1 B

A conductor AB is rotated about O as shown in the figure such that its axis of rotation is parallel to the magnetic field B Bok with uniform angular speed 000 The potential difference between points A and B is given AP QB A 5BowR C zero B 5BomR D None Semi

Two objects are moving in a straight line Their position x versus time t graphs are as in figure The relative velocity of A with respect to B is sin 37 X4 53 B 37 A 1 m s 3 2 2 m s 3 3 m s 4 Zero t

A cyclic process for one mole of an ideal gas is shown in th V T diagram The work done by the gas in AB BC and CA respectively are V V V T Zero RT In RT In V 2 In V RT In V V RT B A T T R T T RT 1 V V Zero V RT1 V V Zero V V

Q4 A uniform solid disk of radius R and mass M is free to rotate on a frictionless pivot through a point on its rim If the disk is released from rest in the position shown by the coppercolored circle What is the speed of the lowest point on the disk in the dashed position Pivot R