Physics Questions

12 For water at 0 C it takes one hour for first 3 mm of ice layer formation How much time will it take for next 6 mm of ice formation 1 2 hour 3 6 hour 2 4 hour 4 8 hour

D Rewrite the following sentences using tenses mentioned in the brackets 1 I have to complete the work on time simple past simple future FEER WEEK n Thre I had to complete 2 The fruitseller will bring fresh fruits simple present simple past 3 Our colony has round the clock security arrangements simple past simple future 4 Ruchika has a new pair of jeans simple past simple future 5 The old woman lived alone simple present simple future That man is a musician simple past simple future

A 10 kmph south B 10 2 kmph north east 10 2 kmph north D 10 kmph east C Paragraph for Questions 11 13 Consider the setup of block wedge and massless pulley as shown The system is completely at rest and all surfaces are inctionless The wedge is tied to the ground by a clipper m 53 Clipper 14kg 11 The reaction force of wedge over the pulley has a magnitude of B 12 g V5 C 4g D None of these 12 The mass of block on the inclined surface is A 5 kg B 4 kg C 4 kg D A 12 g None of these 13 The horizontal force exerted by the clipper which is holding the wedge to the ground is g 10 m s A 24 N 40 N C ON 50 N B D

A ring of radius 5 m is lying in the x y plane and is carrying current of 1 A in anti clockwise sense If a uniform magnetic field B 41 3 is switched on then the co ordinate of point about which the loop will lift up is A 5m

A rigid ball of mass m strikes a rigid wall at 30 and gets reflected without loss of speed as shown in the figure The value of impulse imparted by the wall on the ball will be 30 30

Two wires of same material whose lengths in the ratio 1 2 and area of crossection the ratio 2 1 respectively are connected parallel across a potential difference The ratio of their drift velocity is a 1 1 b 4 1 c 2 1 d None of these

Won t there be potential difference due to 3V battery acr ss the capacitor 14 10V 24 zero 6 92 2 02 wwwwww 1092 3V 3 F HE Find the charge on 3uF capacitor initially it was zero 1 6 C 2 30 C 3 81 C 205

78 A wire frame ABCD has a soap film The wire BC can slide on the frame without friction and it is in equilibrium in the position shown in the figure Find m if T is the surface tension of the liquid a c 271 T1 A D B C b d TI g TI wwwww m

h Cylindrical Gaussian surface is used to calculate electric field intensity for i Point charge ii Hollow sphere iii Infinitely plane Infinitely long uniform charged wire R S

0 Calculate the force of gravity between a 3 kg newborn baby and a 75 kg doctor standing 1 m away 1 3 5 x 10 7 N 2 6 x 104 N 3 2 x 10 6 N 4 1 5 10 N

The electric field at a point inside a long cylinder charged throughout its volume is given by the relation E 3kr Where k is a positive constant and r is the distance from the axis of the cylinder Then choose the correct option s for the charge density p inside the cylinder which depends on ras A por B pxr C pxr D pxr 2

A swimmer can swim in still water with speed v and the river is flowing with velocity v 2 To cross the river in shortest distance he should swim making angle with the upstream What is the ratio of the time taken to swim across the river in shortest time to that is swimming across over shortest distance 11 03

3 A sample of 0 1 g of water at 100 C and normal pressure 1 013 x 105 Nm 2 requires 54 cal of heat energy to convert to steam at 100 C If the volume of the steam produced is 167 1 cc the change in internal energy of the sample is NEET 2018 1 104 3 J 3 84 5 J 2 208 7 J 4

Q 45 For a normal eye the cornea of eye provides a converging power of 40 D and the least converging power of the eye lens behind the cornea is 20 D using this information the distance between the retina NEET 2013 and the cornea eye lens can be estimated to be

ged par voi towards a circular region of uniform magnetic field B perpendicular and into the plane of paper as shown in the figure C is the centre of the circular region If the angle between the line CA and the x axis is 37 and the particle passes through point C then the radius of the circular region R is 1 3 q m mvo qB 6mv V X X X X X A X X X x x 37 x X X 2 4 X 4mvo 5qB 2mvo 2aR X

5 A radioactive isotope a has half life of 2 3 105 yrs The isotope decays into stable 3 A rock sample discovered by archaeologist contains a as 1 15 What could be the possible age of the rock a 9 2 105 yrs b 4 6 105 yrs c 6 9 105 yrs d 1 38 106 yrs O A O B O C C

The mass of a cylindrical body depend on density d of material its diameter D and length L as M d DY LZ If maximum percentage error in measurement of density diameter and length are m n and respectively then maximum percentage error in calculation of mass is O m 1 n O mx yn lz m X n 1 Y Z mx ly nz

half of Initial intensity If a medium is placed between object and objective lens of microscope then resolving power of microscope will 1 Increase 2 Decrease 3 No change 4 Nothing can be prediced In single slit diffraction if we use red light in place of blue light then 1 fringe pattern will ann

2 An equilateral prism of mass m resets on a rough horizontal surface with coefficient of friction A horizontal force F is applied on the prism as shown in the figure If the coefficient of friction is sufficiently high so that the prism does not slide before toppling the minimum force required to topple the prism is F 1 mg 3 2 mg 4 3 a mg 3 umg 4 4

A material when heated suddenly changes its magnetic property at a particular temperature and above this temperature its susceptibility is found to be inversely proportional to the absolute temperature The material may be Only one correct answer A Ferromagnetic B Diamagnetic C Paramagnetic

7 Four identical balls of mass m each are shown The three balls that lie on the ground are prevented from moving by applying horizontal forces not shown The reaction force between the fourth ball placed above and any of the other three ball is 1 3 mg 3 mg 6 8 2 2mg 3 4 mg

32 ALLE When the energy of the incident radiation is incredased by 20 the kinetic energy of the photoelectrons emitted from a metal surface increased from 0 5 eV to 0 8 eV The work function of the metal is 1 0 65 eV 3 1 3 eV 2 1 0 eV 4 1 5 all

9 A block of mass 5 kg is placed over a rough horizontal surface with coefficient of friction 0 1 There is a horizontal force of 13 N is acting on it towards right and another horizontal force F is acting on it towards left Taking g 10 m s the range of F over which block does not slip is 1 8 F 18 N 2 0 F 18 N 3 Any value less than 18 N 4 Any value above 18 N

Which of the following statements is false A C D The energy spectrum of a decay is line spectrum The energy spectrum of B particles is continuous The energy spectrum of y decay is continuous The energy spectra of a y decay are line spectra

A small sphere of mass m made of a material of density d falls from a height h on to the free surface of a liquid of density 3d in a large tank If g is the acceleration due to gravity the maximum depth the sphere reaches in the liquid is neglect viscous forces A Bh C 2h D h 2 h 4

Consider the charge configuration and a Gaussian surface as shown in figure If 1 2 and are net electric flux due to charges 91 92 and 93 respectively then Here q1 92 and 93 all are different and non zero charges qi 0 03 0 2 0 93 Gaussian surface 0

In same phase If AB is incident wavefront Then refracted 4 wavefront just after transmission is D 1 A B 2 A B Biconvex lens 3 A B 4 B A Two source are said to be coherent when 5

2 Light waves a telescope must hav 4 All of the above ater waves For better resolution a 1 Large diameter objective 2 Small diameter objective 3 May be large 4 Neither large nor small The resolving power of

3 A long cylindrical wire of radius a carries a current I distributed uniformly over its cross section If the magnetic field at distances r a and R a from the axis have equal magnitude then 2 a Rr R r 2 1 a 3 a Rr R r 4 a R r

2 A particle is traveling on the path r t with acceleration vector 6t et 0 Initially at t 0 the particle is at the origin with initial speed 4 Its initial velocity is in the positive direction of 1 0 1 i e it is a positive scalar multiple of this vector a What is the initial velocity of the particle b Find r t

If the kinetic energy of an electron gets tripled then the new de Broglie wavelength associated with it will be times of initial value 3 times of initial value times of initial value 3 times of initial value

A radioactive substance named sam decays at a rate of proportional to its size It has a half life of 13 years If there are initially 19 grams of sam how long it will take in years untill there is only 1gram left

2 A rod of uniform charge density and length Li placed vertically as shown A point charge Qo is placed at point O at a distance L from its one end Potential energy of charge Qo is equal to B A Q In 2 4780 Q In2 21TE0 20 480 20 2 080

0 If the light from an ordinary source pass through a polaroid sheet then intensity of lig becomes 1 half 3 one fourth 2 remain same 4 Three fourth

1 When a force is applied on a wire of uniform cross sectional area 3 x 10 m and length 4 m the increase in length is 1 mm Energy stored in it will be Y 2 x 10 N m 1 6250 J 3 0 075 J 2 0 177 J 4 0 150 J

Rewrite the following sentences in negative and interrogative forms 1 Meena is washing clothes 5 The migratory birds are flying off 2 Rohan is playing a football match O Father is relaxing in the study OO OT ON MetaRing to her friend She is 6 The elephant is eating only leaves and grass now 7 The helper is cleaning the house 8 My neighbours are celebrating Christmas with friends this year

We have a galavanometer of resistance 252 It is shunted by a 2 50 wire The part of total current that flows through the galvanometer is given as A I 2 I 11 B I Io 1 C I 4 D I I 3 11 I 11 2 E I

In a single slit diffraction experiment the wid of the slit is made double the original widt How does this affect the intensity of the centr diffraction band large 1 becomes double 2 becomes half 3 becomes one fourth 4 becomes 4 times When a tiny circular obstacle i path of ligh

In double slit experiment if one slit is blocked 35 then what we get on screen 1 Uniform brightness on screen 2 Diffraction pattern on screen 3 Interference pattern remain same 4 Intensity becomes half of Initial intensity

44 unacThree black bodies 1 2 3 have radius r r r3 Emissive powers of black bodies at temperature T are E E E3 Then correct relation between them is CALE Ex E E3 C E E E B E E E3 D E E E P do J CGA74

Two charged particles having charges luC and 1 C and of mass 50 g each are held at rest while their separation is 2m Now the charges are released Find the speed of the particles when their separation is 1m 3 1 ms 1 5 3 ms 10 1 3 1 2 ms NIN 1 4 ms

decreases A Spring balances show wrong readings after they have been used for a long time R Spring in spring balance temporary losses elasticity due to repeated alternating deforming

prediced In single slit diffraction if we use red light in place of blue light then 1 fringe pattern will spread 2 fringe pattern becomes narrow 3 No change 4 Nothing can be prediced Diffraction is possible in waves 1 Sound waves 3 Matter waves Colour appear in CD i 2 Water waves 4 All type

The speed of electromagnetic wave in a medium of dielectric constant 2 25 and relative permeability 4 is approximately Only one correct answer A 1x 108 m s B 2 5 x 108 m s C 3 x 108 m s C 2108mila i

Four conducting plates of same area are placed close to each other Plate 1 2 and 3 are given charges Q 2Q and Q respectively while plate 4 is earthed with the help of switch S which was kept open initially Now if switch S is closed then amount of charge flown from earth to plate 4 is equal to

32 2 What happens when two separate light sourc illuminate a wall 1 Uniform illumination 2 Interference fringes 3 Dark appear 4 Four times intensity of point

A solid body floating in water has 1 of its volume immersed in it What fraction of its volume 5th

of the body A Adiabatic elasticity of a gas is greater than isothermal elasticity Eadiabatic R

Which among the following can emit radiation Excited electron in H atom Excited nucleus Excited electron in Li ion Both 1 and 3

Two bodies A and B having masses m and 2m respectively are kept at a distance d apart A small particle is to be placed so that the net gravitational force on it due to the bodies A and B is zero Its distance from the mass A should be 1 x d 1 2 2 x X d 1 4 3 x d 1 3 d 1 6 Find not force of gravitation 4 x