Physics Questions

A thin dielectric charged layer is placed in uniform electric field After placing it in field field on both side of dielectric is given by diagram If E 20 N C then component of applied field in N C along x axis is 60 E 30 E X

11 A rectangular block of mass M area of cross section A and density D is floating on surface of water If it is given a small vertical displacement in downward direction then the period of oscillation of the mass is 1 2 DL Apag 2 2mL D P B 3 2m V Dg 4 2 DL Pub

angle of second prism should be 176 2 8 3 10 4 4 A beam of light from a souce L is incident normally on a plane mirror fixed at a certain distance x from the source The beam is reflected back as a spot on a scale placed just above the source L When the mirror is NEET 2017 rotated through a small angle 0 the spot of the light is found to move through a distance y on the scale The angle is given by

In column l configuration of charge is given whereas column Il gives variation of field E and potential V on a function of r Match the entries Column l Q1 Uniformly charged spherical shell Q2 Uniformly charged solid sphere Q3 Cylindrical charge having uniform volume charge density p Q4 Column II A1 A2 A3 A4 A5 V4 EA V E R

5 An a c reaches a maximum value of 100 ampere the frequency being 50 Hz Determine the rate of charge of the current in ampere per second when the time is a Ans a 27240 A S b 31420 A S c 0 0 00166 S b 0 01 S c 0 015 S

A very long straight wire carries a current instant when a charge Q at point P has velocity v as shown the force on the charge is 9 a 1 Opposite to OX 2 Along OX 3 Opposite to OY Y O

For a situation shown in figure find the refractive index of glass so that it will suffer total internal reflection at the vertical surface AIIMS 2016 60 3 1 31 4 1 6

An electron enters in a region where magnetic E and electric fields E are mutually perpendicular one another then 1 It will always move in the direction of B 2 It will always move in the direction of E 3 It always possess circular motion also go undeflected

A point source of sound is placed in a non absorbing medium Two points A and B are at the distance of 2 m and 3 m from the source The ratio of intensity of sound at point A and B respectively is 49 WIN LSIN 31

B H Het and O all having the same kinetic energy pass through a region in which there is a uniform magnetic field perpendicular to their velocity The masses of H He and O are 1 amu 4 amu and 16 amu respectively then 1 O will be deflect most 2 H will be deflected most 3 Het and Ot will be deflected most All will be deflected equally charged

A beam of light consisting of red green and blue colours is incident on a right angled prism The refractive index of the material of the prism for the above red green and blue wavelength are 1 39 1 44 and 1 47 respectivel The prism will NEET 2015 Blue Green Red 45 1 not separate the three colours at all 2 separate the red colour part from the green and blue colours 3 separate the blue colour part from the red and green colours 4 separate all the three colours from one another

rying power In a laboratory four convex lenses L L L and L of focal lengths 2 4 6 and 8 cm respectively are available Two of these lenses form a telescope of length 10 cm and magnifying power 4 The objective and eye lenses are respec RPMT 2008 tively 1 L L3 2 L L 3 L L 4 L L principal axis If the power of

ue to surface tension the excess pressure inside a smaller drop is 9 units If 27 smaller drops ombine then the excess pressure inside the bigger drop is 4 units B 1 unit C 2 units D 3 units

A astronomical telescope has objective and eyepiece of focal lengths 40 cm and 4 cm respectively To view an object 200 cm away from the objective the lenses must be separated by a distance 1 50 0 cm NEET 1 2016 2 54 0 cm 3 37 3 cm Th 4 46 0 cm VDSP in 1 Distance between two slits is d 52 where is the wavelength

2 2 3 I 4 In a diffraction pattern due to a single slit of width a the first minimum is observed at an angle 30 when light wavelength 5000A is incident on the slit The first secondary maximum is observed at an angle of NEET I 201 1 7 4 4

Water rises in a capillary tube of radius r upto a height h The mass of water in a capillary r of radius will be 4 m The mass of water that will rise in a A m B 4m C m enc capilar m aque

An engine is moving on a circular path of radius 200 m with a speed of 35 m s While moving the engine blows a whistle of frequency 700 Hz Frequency observed by an observer standing stationary at the centre of circular path will be More than 700 Hz 40 O Less than 700 Hz Equal to 700 Hz O No sound is heard

A large open tank containing water has two holes to its wall A square hole of side a is made at a depth y and a circular hole of radius r is made at a depth 16y from the surface of water If equal amount of water comes out through both the holes per second then the relation between r and a will be 2a r r TU a 2 a 2 T r 2a

4 microscope will decrease but that of telescope In an astronomical telescope in normal adjustment a straight black line of length L is drawn on inside part of objective lens The eye piece forms a real image of this line The length of this image is I The magnification of the telescope is 2 L I 4 1 NEET 2015 1 L 1 L I of the

hs of focal length 0 33m 4 None of the above The focal length of a plano concave lens is 10 cm then its focal length when its plane surface is polished is n 3 1 20 cm 4 none of these 2 5 cm 3 5 cm A combination of two thin lenses with focal lengths f and f respectively forms an image of distant object at dis

Tength of eyepiece Resolving power of a microscope depends upon 1 the focal length and aperture of the eye lens 2 the focal lengths of the objective and the eye 3 the apertures of the objective and the eye lens 4 the wavelength of light illuminating the object lens 4 great

A microscope has an objective of focal length 0 5 cm and an eye piece of focal length 1 cm It is desired to have a magnification of 500 The length of the microscope tube required for this is A 10 cm B 15 cm C 20 cm D 25 cm

metal sphere of radius R density p moves with terminal velocity v through a liquid of nsity o Another sphere of same radius but of density p2 moves through same liquid Its minal velocity will be 0 A P2 V P 0 A 0 V Pl P2 1 0 1 B V D P2 P 0 P 0 V1

The rms speed of a large number of molecules of a gas in a vessel is 600 m s If 25 of the gas leaks out at constant temperature then rms speed of the remaining molecules will be O 450 m s 1 800 m s 1 O 300 m s O 600 m s

the focal length of objective and eye lens of a stronomical telescope are respectively 2m and 5 cm Final image is formed at i least distance of distinct vision ii infinity The magnifying power in both cases will be 4 48 40 2 40 48 3 40 48 4 48 40 pouco

A person can see clearly only upto a distance of 25cm He wants to read a book placed at a distance of 50cm Wha kind of lens does he required for his spectacles and what must be its power 1 concave 1 0 D 3 Concave 2 0 D 2 Convex 1 5 D 4 Convex 2 0 D for sighted ll hole 3 4 mm in oot

An object is placed at a distance of 20 cm in rarer medium from the pole of a convex spherical refracting surface of radius of curvature 10 cm If the refrective index of the rarer medium is 1 and of the refracting medium is 2 then the position of the image is at 1 40 3 cm from the pole inside the denser medium 2 40 cm from the pole inside the denser medium 3 40 3 cm from the pole outside the denser medium 4 40 cm from the pole outside the denser medium

A body is located on a wall Its image of equal size is to be obtained on a parallel wall with the help of a convex len The lens is placed at a distance d ahead of second wall then the required focal length will be AIPMT 2002 1 Only d 4 3 More than d but less than d 7 2 d 2 Only 2 4 Less than d

A proton moves with a constant speed of 50 m s along the x axis through crossed electric and magnetic fields which are perpendicular to each other If the magnetic field is 2 x 10 3 T along the negative z direction what is the corresponding electric field JOL to tartoo A 0 1 V m along positive y direction B 0 1 V m along negative y direction C 1 6 10 18 V m along positive y direction D 1 6 10 18 V m along negative v direction

4 b and c both A person cannot see distinctly at the distance less than one metre Calculate the power of the lens that he should use to read a book at a distance of 25 cm 1 3 0 D 2 0 125D 3 3 0 D 4 4 0 D

A source of frequency fgives 5 beats sec when sounded with a source of frequency 200 Hz The second harmonic of source of frequency fgives 10 beats sec when sounde with a source of frequency 420 Hz The value of fis 38 195 Hz O 410 Hz 205 Hz 390 Hz

A racing car moving towards a hill sounds its horn Driver of the car observes that the sound reflected from the hill has a pitch one octave higher than the actual sound of the horn If sound is travelling with velocity Vo then the car is moving with velocity 2

A biconvex lens forms a real image of an object placed perpendicular to its principal axis Suppose the radii of curvature of the lens tend to infinity Then the image would 1 Disappear 2 Remain as real image still Be virtual and of the same size as the object 4 Suffer from aberrations

14 In the circuit shown the switch S closed for a long time The switch is now opened so that the capacitor gets charged 50 kQ www OV 1 S A Infinite B 1 5s C 1s D 0 67s 10 F 100 k The time constant of the circuit is

A particle perform SHM of amplitude A along a straight 3A from its mean 2 position Its kinetic energy gets increased by an amount mo A due to an impulsive force The new amplitude of the particle becomes line When it is at a distance of O 2A OPA O A L 24

A lens is placed between a source of light and a wall It forms images of area A and A on the wall for its two different postions The area of the sourece of light is 1 A A 2 AJ 2 A A 3 A A 4 A A 2

In Gallilean telescope if the powers of an objective and eye lens are respectively 1 25 D and 20D then for rel vision the length and magnification will be 1 21 25 cm and 16 2 75 cm and 20 3 75 cm and 16 4 8 5 cm and 21 25

A particle perform simple harmonic motion with amplitud A and time period T Average speed of the particle over the time interval during which it travels a distance of A 2 starting from extreme position is 4 A 04A T 0 3A 3A 2T O A 3T 26

1 20 cm 2 40 cm 3 30 cm 4 10 cm A luminous object is placed at a distance of 30 cm from a convex lens of focal length 20 cm On the other side of the lens at what distance from the lens must a convex mirror of radius of curvature 10 cm be placed in order to have and upright image of the object coincident with it 1 12 cm 2 30 cm fo plano 3 50 cm 4 60cm Convex lens of focal lenght f is silvered It will behave as

If there had been one eye of the man then 1 Image of the object would have been inverted 2 Visible region would have decreased 3 Image would have not been seen three dimensional 4 b and c both

A bar of 2 m long with negligible weight rests in horizontal position on two smooth inclined planes as shown in Fig Determine the distance x at which the load Q 100N should be placed from point B to keep the bar horizontal P 200N 0 5m 307 2m Q 100N 45 B

The image for the converging beam after refraction through the curved surface is formed at n 1 n 3 2 30 R 20cm 1 x 40 cm 2 x 40 3 cm 40 3 3 x cm 180 7 4 x cm

1 w 8 2 8 00 When white light passes through the achromatic combination of prisms then what is observed Only deviation 2 Only dispersion 4 None of the above 3 Deviation and dispersion of ongle of minimum deviation of a prism in air and when dipped in water will be 3 u 3 2 ar

3 2 4 1 A plate in the form of a semicircle of radius a has a mass per unit area of kr where k is a constant and r is the distance from the centre of the straight edge By dividing the plate into semicircular rings find the distance of th centre of mass of the plate from the centre of its straight edge 1 3a 2 2 a 2 3 3a 4 a n

3 the total momentum of the ball and the earth is conserved 4 the total energy of the ball and the earth remains the same A particle of mass m moving with a speed v hits elastically another stationary particle of mass 2m in a fix horizontal circular tube of radius r Find the time when the next collision will take place

The refractive indedx of a prism for a deviation the angle of incidence will be 1 30 monochromatic wave is 2 and its refracting angle is 60 For minimum 2 45 3 60 4 75 of monochromatic light is incident at one surface of a equilateral prism Angle of incidence is 55 and

1 3 50 2 6 25 3 0 03 4 none of these All the listed things below are made of flint glass Which one of these have greatest dispersive power 1 prism 4 all have same w 2 glass slab 3 biconvex lens uplongth 4000 is incident at small angle on a prism of apex angle 4 The prism has n 1

A Galileo telescope has an objective of focal length 100 cm magnifying power 50 The distance between the t lenses in normal adjustment will be 2 100 cm 3 98 cm 4 200 cm 1 150 cm The convex lens is used in

Three large conducting charged sheets are kept parallel to each other as shown in figure Net force experienced by a charge q placed between plates A and Bis A B C q 3C 1C Zero X Towards right Towards left 2C Both 2 3 are possible

In the figure given below there are two convex lens L and L having focal length of f and f respectively The distance between L and L will be 1 f 2 L 3 f f 4 f f