Basic Physics Questions and Answers

A beam of light is incident on a glass plate at an angle of incident 60 The reflected ray is polarised what is the angle of refraction when angle of incidence is 45 Only one option is correct A O sin 3 2 BO cos1 3 2 C O sin 1 6 D O sin 1 3

mathonso Q8 27 July 2021 Shift 2 mathongamathongs mathonga What will be the magnitude of electric field at point O as shown in figure Each side of the figure is I and go perpendicular to each other A q mothon CID mathongo 24 q B hathor q 0 I mathor 29 I q Eathogo 1 I 2q 4mo 21 mathongo 2 mathongo G 2q mathongo 1 1 9 4neo Pongo 2 4 2 2 2 1 mq 3 4mco 21 4 q Hmathongo mothongo mathongo mathongo mathongomathongo mathongo mathonge mothongo mathongo mathongo mathongs mathongo mathongo mathonga mathongo mathonge mathango mathongo mathongo mathango mathongo mothongo mathongo mathongo mathongo mathongo mathongo mathongo mathongs mathongo mathango mothongo

A block of mass m is kept on an inclined wedge of mass M The angle of inclination of the wedge is 0 All the surfaces are frictionless A horizonta force of magnitude Fis applied horizontally on the small block as shown in the figure Force required to keep the block in equilibrium with respect to the wedge is 1 M g m E tane M 2 smooth Mm M m gtano

b An excited atom releases its excess energy by emitting a photon of characteristic frequency v The average period that elapses between the excitation of the atom and the time it radiates is 10 ns Find the uncertainties in the i energy ii frequency and iii wave length of the photon

140 A large non conducting sheet M is given a Q 140 uniform charge density Two uncharged small metal rod A and B are placed near the sheet as figure Then which is not correct M 1 M attracts A 2 M attracts B 3 A repels B 4 B attracts A A B at araferer g at utat ve A Betty feargar fera ad 1 M A at maffa 2 M B at arraffe 3 A B at fal 4 B A at straffe Exams

Two identical simple pendulums are coupled by spring of spring constant k Write the equation of motion for this coupled oscillator and discuss the normal modes of this oscillator auc kfnfudifin yfua f y and 1 34 yfulcc

A disc of radius r 2cm attached with a horizontal axle OA is rolling without sliding on a circular track of radius R 10 cm as shown In the process the centre of the disc moves with a constant speed 10 cm s Find the angular acceleration in rad s of the disc in rad s V R O R

Always less than its magnitude A Always greater than its magnitude Always equal to its magnitude May be greater than its magnitude Solution Answer 4 B The magnitude of component of a vector A can be greater tha

of focal 35 A wire is bent in the shape of a right angled triangle and is placed in front f as shown in the figure Which of the figures shown in the four options qualitatively represent s thes of the image of the bent wire These figures are not to scale A C a 45 0 a 45 B D 45 JEE Advance Z

proportional to the distance y from its nearest bank v becomes maximum in the middle and is equal to vo A boat is moving in the river with a constant velocity u relative to the water and perpendicular to the current Find the drift of the boat Width of the river is d 3 2u d 2 X vod 4u vod 31

Figure shows the transfer characteristics of a CE amplifier which of the following is incorrect statement 0 0 6 V 2 V O At V 0 4 V transistor is in cut off mode At V 1 V it can be used as an amplifier O At V 0 5 V it is in active state O At V 3 V it can be used as a switch turned on

20 Graph 1 and 2 in the figure shows graph of two motor cyclist moving along same line in same direction 25 Motorcyclist 2 starts from 25 m behind motorcyclist 1 If maximum distance in meter between the motorcyclist before they meet for the first time is d 150 in meter is equal to 15 10 5 10 20 30 40 50 X

3 A ball of mass 1 kg attached with string of length 10 m is free to rotate on smooth horizontal plane is subjected to constant force of 2 i 1 N What should be the minimum velocity of projection at position shown in figure so that it complete full revolution 1 A 10 ms 10m B 2 5 ms YA 45 X C 4 5 ms D 6 ms

The relative permittivity of distilled water is 81 The velocity of light in it will Given 1 mathongo mathongo mathongo 1 4 33 x 107 m s 2 2 33 107 m s 3 3 33 x 107 m s 107 mathongo mathonga mathongo mathongo mathonge mathongo

14 A tuning fork vibrating at frequency 800 Hz produces resonance in a resonance column tube The upper end is open and the lower end is closed by the water surface which can be varied Successive resonances are observed at lengths 9 75 cm 31 25 cm and 52 75 cm Calculate the speed of sound in air from these data nu Solution For the tube open at one end the resonance frequencies are where n is a positive odd integer If the tuning fork has a frequency v and l l l are the successive lengths of the tube in resonance with it we have nu 41 n 2 v 412 n 4 v 41 giving 13 12 1 1 1 2v 4v V V V 2v

A simple pendulum of mass m length I and charge q suspended in the electric field produced by two gu conducting parallel plates as shown The value of deflection of pendulum in equilibrium position will be mathon mathongo mathongo Electrostatics Questions with Answer Keys mathongo Medium X K V mathongo natnonge d Ex 1 tan ton 1 1 m W nath Vomathongo q air athongo 9 C V V mathon MathBole TohMathonGo mg C C d t nge 9 C V V www mathongo com hongo mathongo mathongomathongo mathongo mathango mathongo mathongo mathongo mathongo JEE Main 2021 July Chapter wise Question MathonG mathonga mathongo mathongs mathongo mathongo mothor mathongo mathongo matha 3 8 mathongo mathongo

An electron is confined to a space of diameter 10 10 m has a minimum kinetic energy of 5x 10 18 J What is the minimum kinetic energy of an electron confined to a space of diameter 0 5 x 10 10 m A 2 5 x 10 8 J B 5 x 10 18 J C 10 7 J 2 x 10 17 T

II The distance between two points on the ground was measured with 30 m chain and found to be 1500 m The same distance was measured with a 20 m chain and found to be 1450 m If the 30 m chain was 5 cm too short what was the error in the 20 m chain

79 Due to induced emf of the metal rod PQ Q 79 for moving at speed v in transverse magnetic field as shown in figure charge on each capacitor is XXX XXX Bx xxxxxx V xxxxxx x xx xx x xxxxxx 1 Zero 2 BCLv xxxxxx P Bx xxxxxx x xxx XXX x xx xx x 1 BCL v PQ afta fama

Q5 25 July 2021 Shift 2 mathonge mathongo mathonga mathongo mathongo Two ideal electric dipoles A and B having their dipole moment p and p respectively are placed on a plane hon with their centres at O as shown in the figure At point C on the axis of dipole A the resultant electric field is making an angle of 37 with the axis The ratio of the dipole moment of A and B is take sin 37 mathongo mathongo mathonge mathongo mathongo mathongo 10 10 2000 00 2 mothongo 2 thongamathongo mathongo mathongo mathongo mathongo mathange

Keeping the banking angle of the road constant the maximum safe speed of passing vehicles is to be increased by 10 The radius of curvature of the road will have to be changed from 20 m to 1 16 m 2 18 m 3 24 20 m 4 30 5 m

the linear density of a wire under tension t varies linearly from to 20 Calculate the time that a pulse would need to pass one to the other The length of the wire is I ONO 24 3 T 2 2 T 3 4 12 2 14 2 2 3 3 2 12 2 43 2 1 3 2 12 2 TH 3 2 4 1 T 1

Whenever a hydrogen atom emits a photon in the Balmer series 1 It may emit another photon in the Balmer series 2 It must emit another photon in the Lyman series 3 It may emit another photon in the Paschen series 4 It need not emit any more photon

NEET PHYSICS Q 140 The additional kinetic energy to be provided to Q 140 a satellite of mass m revolving around a planet of mass M to transfer it from a circular orbit of radius R to another of radius R R R is 1 GmM 2 GmM 1122 1 1 R R 3 2GmM R R 4 GmM 1 1 R R All India Major Test Series Phase l II Major Test 30 24 15 06 2020 Int R R aite R from a R R R for a fee for affa 1 GmM 2 GmM 3 2GmM RR 4 GmM 1 R R R R R R eft ical Exams

Q 150 S S are two coherent sources of sound Q 150 S HT Safar having no initial phase difference The velocity of sound is 330 m s No minima will be formed on the line passing through S and perpendicular to the line joining S and S if the frequency of both the sources is Ps 1 50 Hz 3 70 Hz 3ml 2 60 Hz 22 4 80 Hz treff m s 1 fret efter 330 2 at f fafa af argfer staff In Tutute 1 50 Hz 3 70 Hz 3m 1 14 S 2 60 Hz 4 80 Hz

All India Major Test Series Phase l II Major Test 38 32 01 08 2020 40 cm NEET PHYSICS 2 86 Radius of curvature of a concave mirror is Q 86 40 cm and the size of image is twice as that of object then the object distance is 1 60 cm 2 20 cm 3 40 cm 4 30 cm fafanya 1 60 cm 3 40 cm 2 20 cm 4 30 cm

The ratio of earth s surface area as covered by two communication satellite moving 1 synchronously in equatorial plane with orbital speed of times that of 2 required orbital speed near earths surface is No 4 5 5 2 5 4 2 5 times and 3 5

The given wave function for the hydrogen atom is 100 210 3211 Here nim has 1 7 and m as principal orbital and magnetic quantum numbers respectively Also nim is an eigen function which is normalized The expectation value of L in the state is 9 a 11 b 11h c 20 11 d 21

1 18 A particle moves in a straight line with the velocity curve shown in figure 1 156 Draw approximate acceleration vs time and displacement vs time curves Consider x 0 at t 0 v m s A 1

At a place A intensity of geomagnetic field is 39 8 A m and angle of dip is 68 At another place B intensity 43 8 A m and angle of dip is 72 Compare the horizon 1 tal components of geomagnetic intensity at these tw places ratio 1 101

Find a in degrees 6 11 5 Round to the nearest hundredth Enter

An electric dipole is placed on x axis in proximity to a line charge of linear charge density 3 0 10 C m Line charge is placed on z axis and positive and negative charge of dipole is at a distance of 10 mm and onge 12 mm from the origin respectively If total force of 4 N is exerted on the dipole find out the amount of positive or negative charge of the dipole mathongo mothongo mathongo mathongo mathongo 1 815 1nCngo mathongo mathongo mathongo mathongomathonge 2 8 8 C mothongo mothongo mothongo mathongo mathongo mathonge 3 0 485mC 4 4 44 Congo mathongo mathongo mathongo mathongo mathonga

a box of f it inside a teak wood sensitive magnetic instrument can be shielded very effectively from outside fields by placing Earth s magnetic field inside a closed iron box as compared soft iron of high permeability b plastic material d a metal of high conductivity more

A charged particle moves in a gravity free space without change in velocity If and B represents the electric and magnetic field respectively this region may have 1 0 B 0 2 E 0 B 0 3 and B are inclined at 45 with each other 4 Both 1 and 2

The approximate electric potential energy due to the electric repulsion between two nuclei of C 12 when they touch each other at the surface is take radius of C 12 nuclei as 2 52 fm 1 64 x 10 12 J 02 64 x 10 12 J 03 2 x 10 16 J 2 8 10 12 J

The Substance Abuse and Mental Health Services Administration SAMHSA 2017 estimates that 10 9 of the population of the United States age 18 24 had an episode of depression in the previous 12 months Suppose a researcher takes a random sample of 225 United States adults aged 18 24 Determine the value of the sample proportion p such that 2 of samples of 225 United States adults age 18 24 are greater than p You may find software or a z table useful Give your answer precise to three decimal places

A pipe of length 1 5m closed at one end is filled with gas and resonates in its fundamental mode with a tuning fork Another pipe of same dimension filled with air resonates in its fundamental mode with same tuning fork If experiment is performed at 30 C speed of sound in air is 360 m sec the velocity of sound at 0 C in gas is ONO 580 m sec 680 m s 880 m sec none

Find in degrees V113 8 0 7 degrees Round to the nearest hundredth E

You are tasked to reduce the following circuit to its Thevenin equivalent What is the value of voltage VTH and resistance RTH of this Thevenin equivalent circuit The values of various circuit elements are R 5 92 R 10 S2 R3 2 S2 R4 6 is 5A and Vs 7 V Suggestion Use mesh analysis R R3 www R 22V RTH 492 14 25V RTH 392 VTH VTH VTH 19V RTH 492 www 2 RA o a b

The diameter of a cylinder is measured using a vernier calipers with no zero error While measuring diameter of a cylinder it is found that the zero of vernier scale lies between 5 10 cm and 5 15 cm of the main scale Vernier scale has 50 divisions whose total length is equivalent to 2 45 cm The closest division of the vernier scale that almost coincides with a main scale division is 24th VSD but this 24th VSD actually falls slightly to the right of the main scale division The diameter of cylinder may be each MSD 0 05cm A 51 238 mm B 51 236 mm C 51 242 mm D 51 246 mm

B 1 Teola is applied in x 0 region a metallic Ming radius I m is moving with const v 1m s along rasis induced emf At 05 center ring is at x 1 in sing at t is IN LV 2TTV DV 1 0

a particle consists of 1 2 protons only 2 2 protons and 2 neutrons only 3 2 electrons 2 protons and 2 neutrons 4 2 electrons and 4 protons only

Q 27 Your Answer 1 2 Option 1 3 2 Option 2 1 2 If the angles of dip at two places are 30 and 45 respectively then the raito of the horizontal components of earths magnetic field at the two poles will be Option 3 1 3 Option 4 1 2 Correct Answer 3 2 Solution As we have learnt A 1

The conducting shells A and B are arranged as shown below If charge on the shell B is q then electric flux linked with the spherical Gaussian surface Sis 2r B

In the arrangement shown all surfaces are smooth and string and pulley are light Mass of A is twice that of B The free end of F Tiba B A the string is pulled with a force F equal to half the weight of A a When F is horizontal a 0 ag 0 b When F makes an acute angle with horizontal 0 a 0 c When F makes an acute angle with horizontal a 0 AB 0 d When F makes angle 60 with horizontal aR 4a

A sensitive magnetic instrument can be shielded very effectively from outside fields by placing it inside a box of a teak wood c soft i Farth s magnetic field inside a closed iron box as compar 14 tiron of high permeability b plastic material d a metal of high conductivity

Two discs of same mass and same thickness have densities as 17 g cm and 51 g cm The ratio of their moment of inertia about their central axes is 1 3 113 31 2 4 2 3 3 7

Find out the mass of Uranium required per day to operate 0 95 MW nuclear power plant using 92U235 fission 1 2 3 1gm 10 kg 100 kg 100 gm

A rabbit running around a circular path has made one quarter of the distance around the path At this moment the distance between the rabbit and the starting point is 300m What is the radius of the path

The population of a certain region grew from 19 7 million in 2005 to 23 3 million in 2012 a Find a function of the form P t Cet that models the population growth of the region Here t is the number of years since 2005 and P t is in millions Round your k value to 3 decimal places P t Preview PHONE b Use your model to predict the population of this region in 2017 Round your answer to the nearest tenth of million million people