Basic Physics Questions and Answers

7 Two block of masses m and m are connected with the help of a spring of spring constant K initially the spring in its natural length as showsn A sharp impulse is given to mass m so that it acquires a velociy v towards right If the system is kept an smooth floor then find the maximum elongation that the spring will suffer mi k 0000000 m2 Vo

4 3 Example 24 A bird in air is diving vertically over a tank with speed 5 cm s base of tank is silvered A fish in the tank is fing upward along the same line with speed 2 cm s Water level is falling at rate of 2 cm s Take H on Column I cm s A D B C Speed of the image of fish as seen by the bird directly Speed of the image of fish formed after reflection in the mirror as seen by the bird Speed of image of bird relative to the fish looking upwards Speed of image of bird relative to the fish looking downwards in the mirror Column II P 8 Q 6 R 3 S 4 Example 26 Quarter p falls on th a light E whic Ans A Q B R C P D S

Light of wavelength 500 nm falls on a metal of work function 1 9 eV The stopping potential in this experiment of photo electric effect is O 0 34 V O 0 43 V O 0 58 V O 0 28 V

16 In the network shown the potential difference between A and B is R r r r 192 E 3 V E 2 V E3 1V E A R r www E B E 1 1 V 2 2 V 3 3 V 4 4 V wer 8 Pusa Road New Delhi 110005 Ph 011 47623456

When wave of wavelength 0 2 cm in made to incident normally on a rectangular slit of width 0 004 m then semiangular width of central maxima of diffraction pattern will be 30 O 37 O 45 O 60

5 Two nucleons are at a separation of one fermi Protons have a charge of 16 x 10 19 C The ne nuclear force between them is F if both are neutrons F if both are protons and F3 if one is proton and the other is neutron Then 2005 a F F F3 c F F Fa b F F F3 DE ESE

A circular disc of radius R is removed from a bigger circular disc of radius 2R such that the circumferences of the disc coincide The centre of mass of the new disc from the centre of bigger disc is 1 R 3 R 2 R2 R 3 17

A conductor of area of cross section A having 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 along with their random motion are moving with average velocity v A current I flows in the conductor If is the current density then O nqV in the direction opposite to charge flow Oj nqv in the direction perpendicular to charge flow Oj nqv in the direction of charge flow O n qV in the direction of charge flow

Hypertonic urine formation is a characteristic of kidneys of Fishes and amphibians Amphibians and reptiles Reptiles and birds Birds and mammals Correct Answer nammals Your Answer XX Reptiles and birds

answer out of which ONLY ONE is correct choice questions Each question has 4 choices A B C and D for its 1 If a force F 31 43 5k Newtons is acting on a particle moving on a circle of radius 2m with a speed increasing at the rate of 2ms2 All points on the circle satisfy the equation 3x 4y 5z 0 The power of the force on the particle Increases with time C Is constant B Decreases with time D Zero

In figure block 1 is one fourth the length of block 2 of mass also one fourth No friction exists between block 2 and surface on which it rests Coefficient of friction is u between 1 2 Find the distance block 2 moves when only half of block 1 is still on block 2 Block 1 and block 3 have same masses 2 4m

A satellite is revolving round the earth in an orbit of radius r with time period T If the satellite is revolving round the earth in an orbit of radius Ar Ar r with time period T AT AT T then find 3 AT T 3 Ar 2 r Ar 2 4 2 Ar 3 r 2 Ar

18 An ideal gas expands from state A to B as shown in the figure T P A M B Choose the incorrect option 1 Work done by the gas is positive Work done by the gas continuously increases 3 Work done by the gas is negative 4 TA TB Now Dolbi 410005 Phone 011 47602456

Light with an average flux of 10 w em falls on a non reflecting surface at normal incidence having surface area 40 cm The energy received by the surface during time span of 2 minutes is O 24 kJ O240 J O 12 kJ

WY SECI PHY SECH PHY SEC Question 11 Mul Select Type CHEM SECI CHEM SEC CHEM SECH MATH SEC MATH SECE MATCH QUESTION STATU A dumbbell is constructed by fing small identical bolls at the ends of a light rod of length The dumbbel monds vertically in the corner formed by a frictionless wall and frictionless floor After the bottom end is slighty pushed towards the gre the slide value of which of the following quantities vanish when the upper ball is losing contact with the wall L

A toy car is moving on a circular path of radius 10 m on an inclined plane of inclination 30 The coefficient of friction between the tyres and the inclined plane is The maximum constant speed of car such that car does not slip is 5 P ms Assume that width of the car is negligible with respect to radius of circular path Find the value of P g 10m s 3 30

ion ends upon the length of th Assertion In the phenomenon of mutual induction self induction of each of the coil persists Reason Self induction arises due to change in current in the coil itself In mutual induction current changes in both the individual coil

Two particles having position vectors 61 101 metres and 2 101 6 metres are moving with velocities V 81 61 m s and v 2a 14 m s If they collide after 2 seconds then value of a is 2 4 1 2 3 6 4 8

A metal wire of length L and area of cross section A is attached to a rigid support Another metal wire of length L and of the same cross sectional area is attached to the free end of the first wire A body of mass M is then suspended from the free end of the second wire If Y and Y are the Young s moduli of the wires respectively the effective force constant of the system of two wires is a c X Y A 2 XL Y 4 X Y A 8142 2 124 b d A 44 2 X12 1 2 A 424 1 2

SolveLancer Test A fair die is thrown 8 times Find the probability that a prime number will ap 36b png maximum three times on the throws SolveLancer Test 8 a 90 8 b c d 8 8 93 62

A object is moving parallel to principal axis of a concave mirror of focal length 100 cm Distance between and principal axis is 1 cm The langent of angle between velocity of image and principal axis is nearly A 0 01 C 0 03 B 0 02 D 0 04

If the air of weight w is filled in an empty balloon which weighs w the weight of the balloon will become w Suppose the density of the air inside and outside the balloon is same then A B C D W W W W2 W w w W W Correct Answer W2 W1 W

Water is flowing continuously from a tap having an internal diameter 8x10 m The water velocity as it 3 1 leaves the tap is 04 ms The diameter of the water stream at a distance 2 x 10 1 m below the tap is close to

1 67 A particle of mass m and charge q moves along a diameter of a uniformly charged sphere of radius R and carrying a total charge Q Find the frequency of oscillations of the particle if the amplitude does not exceed R Ans 9Q mp 2 4 En

A block of mass 10 kg is kept at rest on a rough inclined surface as shown The net contact force on m is 10 m s 100 N 80 N O 60 N O 40 N m 0 75 37 Marks 4 1

9 Assertion A Sea divers wear special suits Reason R There is no effect of gravity under the sea PATH A Both A and R are true but R is the correct explanation of A ab d B Both A and R are true but R is not the correct explanation of A C A is true but R is false D A is false but R is true

43 Two spheres of masses m and 2 m are separated by distance d A particle of mass is projected straight m 5 from 2 m towards m with a velocity vo Which of the following statements is correct a Velocity of the particle decreases constantly b Velocity of the particle increase constantly c Acceleration of the particle may become momentarily zero d The particle never retraces its path

SolveLancer Test A machine is used to produce magnetic field which creates a magnetic flux number of magnetic field lines when passed through a copper coil varying with time t as p 9 at t Tm The resistance offered by the coil is 9 0 The maximum values of current will be induced in the coil during the interval t 0 to t 3 0 s The value of this peak current will be Here a 4 00 s and 12 00 s 2 SolveLancer Test 3 a b c d a b C 3 A 6 A 4 A 12 A

118 The driver of an express train suddenly sees the red light signal 50 m ahead and applies the brakes If the average deceleration during braking is 10 0 ms and the reaction time of the driver is 0 75 sec the minimum speed at which the train should be moving so as not to cross the red signal is 24 355 300 do 65 Sodo 50 m draud est Jog ros Soteri rb d w 3r C o Sob o r k dom do 10 0 ms Sabato d v jodar sodu 0 75 sives san Ja totes ad or jo 30 pardodsys sbs 58 1 27 Km hr 123 7 Kmb 2 115 Km hr 741 83 Km hr

Intensity of light 50 Two SHMs in same direction are represented by y asinot and y2 asin ut 8 When they superimpose the initial phase difference of the resultant SHM is 4158 2 28 3 8 10 No 2 Ha K4 s nts

The two compounds given below are H H D I Br CI O Enantiomer O Identical O Meso compound O Diastereomers I D CI Br H H

A ball is projected from the point O with velocity 20ms at an angle of 60 with horizontal as shown in figure At highest point of its trajectory it strikes a smooth plane of inclination 30 at point A The collision is perfectly inelastic 20 ms 60 130 A The maximum height from the ground attained by the ball is 15 m The maximum height from the ground attained by the ball is 18 75 m The maximum height from the ground where ball collide on inclined plain is 15m The maximum height from the ground where ball collide on inclined plain is 18 75m

18 In a series L C R circuit R 200 22 and the voltage and the frequency of the main supply is 220 V and 50 Hz respectively On taking out the capacitance from the circuit the current lags behind the voltage by 30 On taking out the inductor from the circuit the current leads the voltage by 30 The power dissipated in the L C R circuit is

119 When a mercury thermometer is inserted in a pot of hot water and the reading is recorded what temperature is being recorded 1 Average temperature of water and surrounding 2 Average temperature of thermometer 3 Average temperature of water and thermometer 4 Temperature difference between water and surrounding

A particle of mass m kinetic energy K and momentum P collides head on elastically with another particle of mass 2m at res Match the following after collision Column I A Momentum of first particle B Momentum of second particle C Kinetic energy of first particle D Kinetic energy of second particle Column II p 3 4P 9 K 9 r P 3 8K 9 s t None

3 When a force F is applied to a mass m its acceleration is 6 m s If the same force is applied to another mass m it gives an acceleration 3 m s If the two masses are tied together and if the same force is applied to the combination it gives an acceleration 5 05 F50 m go or a stom 3 30 3 30 6 5 ed ory 55g boss 505 party wos 3 1 5 m s my go do 54 dos ad wos son 1 3 m s 2 2 m s no dom 4 1 m s2

96 The vectors A B and C are such that A BLIC 21A and A B C 0 The angles between A and B Band C respectively are 3010 A B 0 C 3000 A B dg B C 1 90 135 4g Soo 2 90 45 A B C 2 A A B C 0 500m 3 45 135 4 45 90

18 Two blocks of mass 1 kg and 2 kg respectively are connected by a spring and kept on a frictionless table The blocks are pulled apart so that the spring is stretched and released from rest At a certain instant of time the block of mass 1 kg is found to be moving at a speed 2 m s What must be the speed of the other block at this instant a 1 m s c 4 m s b 0 5 m s d 0 25 m s J K CET

102 A solid sphere and a thin spherical shell of same radius rotate about their diameters with same angular momentum but with different angular velocities IfM and M are the mass of solid sphere and hollow sphere and if their angular velocities are in the ratio 1 2 then 2 og tons as to eat fogfee and g tio idom st das dag 3 2001 da no camin data dago M M cu n e dog esno digobo ard s dos de page 1 2 would sya M M Daje

3 A stone is dropped from the top of a tower of height 45 m One second later another stone is thrown down from the top of the same tower Both stones reach the ground at the same time If g 10 m s magnitude of the initial velocity of the second stone is 418 w growd 45 s Dey Jood 8008 300d s 55 dog 5 55 od 2 805 od 8008 050ards Bodo orday dowo Joross g 1055 s wond Bods row 0 3K 50rm 2 12 5 m s 1 25 m s 3 8 m s 16 mis

Two parallel metal plates A and B separated by a distance 25 cm are connected to an ammeter Photons of energy 3 28 eV are incident on the photosensitive plate A of threshold wavelength 5000 A The minimum value of the magnetic field to be applied parallel to the plates so that the current through the ammeter becomes zero is Bx10 5 T Then the value of B is mass of electron 9 0x10 31 kg charge of electron 1 6 10 19 C

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Two longparallel wires carry currents I and I2 11 12 When the currents are in the same direction the magnetic field at a point midway between the wires is 10ur If the direction of 12 is reversed the field becomes 40 T The ratio 11 12 is 1 5 2 2 5 3 3 4 3 4 3 2

A man is carrying a block of certain material density 1000 kg m weighing 1 kg in his left hand and a bucket full of water weighing 10 kg in his right hand He drops the block in the bucket How much load does he carry in his right hand now as 31 kg aroo ne as ago 1000 kg m ne Sels Dodo aseutu sud 30 u ardo ud u de Jod word Options 1 9 kg 2 Bass 3 10 kg 11 kg 12 ka 306 10 kg do eve tas AP EAMCET 2020 AP EAMCET 2020 71 119

Example 24 Monochromatic light is incident on a plane interface AB between two media of refractive indices n and n n2 n at an angle of incidence 0 as shown in fig 33 The angle 9 is MEDIUM I A D G MEDIUM III 13 MEDIUM II n E F B Fig 33 infinitesimally greater than the critical angle for the two media so that total internal reflection takes place Now if a transparent slab DEFG of uniform thickness and refractive index n is introduced on the interface as shown in figure show that for any value of n3 all light will ultimately be reflected back again into medium II Consider

Board Competitive Exams A ball is dropped from an elevator moving upware ation a ding

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A rod of mass m and length L 50 3m is hinged in plank of same mass m The plank is kept on a smooth horizontal surface and rod makes with the vertical The system is released from 0 0 Find the velocity in m s of plank when the rod makes 0 180 g 10 m s Find the value of v 2 m

their potential energies What is the kinetic energy of a body of mass 1 kg moving with a speed of 2 m s Is potential energy a vector or a scalar quantity 11 kept at heights of h and 2h respectively What will be the ratio of 1001

Zero Marks 0 In all other cases If a charged spherical conductor of radius 10 cm has potential V at a point distant 5 cm from its centre then the potential at a point 15 cm away from the centre is V a find a