Physics Questions

Mark the correct statement A The magnitude of the velocity of a particle is equal to its speed B The magnitude of average velocity in an interval is equal to its average speed in that interval C It is possible to have a situation in which the speed of a particle is always zero but the average speed is not zero D It is possible to have a situation in which the speed of the particle is never zero but the average speed in an interval is zero A A Correct Not Marked By You

Four metallic plates each with a surface area A are placed at a distance d from each other as shown in the figure If points A and B are connected with a battery of emf V then the charge on the plate a will be O 3 A V d b C d Read More B

A plano concave lens having index of refraction 1 50 is placed on a flat glass plate as shown in Figure P37 64 Its curved surface with radius of curvature 8 00 m is on the bottom The lens is illuminated from above with yellow sodium light of wavelength 589 nm and a series of con centric bright and dark rings is observed by reflection The interference pattern has a dark spot at the center sur rounded by 50 dark rings of which the largest is at the outer edge of the lens a What is the thickness of the air layer at the center of the interference pattern b Calcu late the radius of the outermost dark ring c Find the focal length of the lens

A particle starts moving from the point 1 2 3 under velocity li 23 3k for two seconds After that it moves under velocity 11 2j 3k for the next two seconds What is the coordinate of the final point A 5 2 5 C 1 2 15 A B 4 Correct Skipped By You B 5 2 15 D None of these

A particle moves from rest at A on the surface of a smooth circular cylinder of radius ras shown At B it leaves the cylinder The equation relating a and Bis a 3 sin a 2 sin c 3 sin 2 cos a 82 17 b 2 sin a 3 cos d 2 sin 3 cos a B

A prism of refractive index n and another prism of refractive index n are stuck together as shown in the mothong figure n and no depend on A the wavelength of light according to the relation A mothongo mathongo mothongo mathongamathongo n 1 2 and n 1 45 1 mathonge mathongo Amathonga mata The wavelength for which rays incident at any angle on the interface BC pass through without bending at that mathongo mothongo mathongo mathonga mathongo mathongo Ray Optics Questions with Answer Keys interface will be nothongo C170 e 14 10 8 x 107 nm D mathongemathongs 90 1 8 x 10 14 hongo 1 MathBole TohMathonGomathongo www mathongo com mothongo mathongo JEE Main 2021 July Chapter wise Questions MathonGo mathongs mathonga mathongo

8 Half life of a radioactive substance is 2 34 minute It is produced at a constant rate of 10 nuclei per sec How soon after in minute the beginning of production will its activity be equal to 7 5 10 disintegration per sec

A uniform chain of length L and mass M is lying on a table and of its length is hanging vertically down over the edge of the table If g is acceleration due to gravity the work required to pull the hanging part back on the table MgL 16 Read More MgL 32

wo blocks of mass 10 kg and 5 kg are connected with a light string which is assing over an ideal pulley attached with a fixed smooth wedge If the system is eleased from rest then the acceleration of the blocks will be 5 kg 37 O 5 m s 0 m s 2 m s Read More 10 kg

A particle is subjected to different types of accelerations in different initial condition position vector at t 0 V initial velocity a acceleration Column I Column II 1 F i j 11 F 21 III 1 IV 10 10 O II ii Q III ii P P Q iii V 101 R iv V 51 10 S In which of following case particle moves in straight line path O 1 i Q IV iv S i ii V 0 v 2 Column III a 21 3j a 5j a 10 a 21

A soap film n 1 33 is contained within a rectangular wire frame The frame is held vertically so that the film drains downward and forms a wedge with flat faces The thickness of the film at the top is essentially zero The film is viewed in reflected white light with near normal incidence and the first violet 420 nm interference band is observed 3 00 cm from the top edge of the film

A battery of emf 20 V is connected to resistances as shown in figure The potential at the point C will be 302 www O 10 V 08V O 6 V www 192 wwww 322 B wwww 392 www Read More 192

Use phasor addition to find the resultant amplitude and phase constant when the following three harmonic functions are combined E sin wt 6 E 3 0 sin wt 77 2 and E3 6 0 sin wt 4 3

This section contains 35 O 68 Hz A set of 16 tuning forks are so arranged that each produce 4 beats with the previous one If the frequency of last tuning fork is double that of first the requency of third tuning fork is O 60 Hz Read More O 120 Hz questions Each question has 4 choices

A thin equiconvex glass lens 1 5 of radius of curvature R and a thin plano concave lens u 1 4 are kept in contact and the plane surface is silvered This lens system is placed in air When a point object is placed at a distance 20 cm from the lens system on its principal axis the image formed by the lens system coincides with the object Then the value of radius of curvature R is A 12 cm C 24 cm B 18 cm D 30 cm 1 5 H 1 4

In the following figure C 5 F C C 10 F and 20 V Initially the switch S is connected to point A until capacitor C is fully charged Afterwards switch is thrown to left side and connected to point B The charge on capacitor C after equilibrium is reached will be Options 1 40 C B HE A 8 20v

A block of mass m at the end of a string is whirled round in a vertical circle of radius R The critical speed of the block at the top of its swing below which the string would slacken before the block reaches the top is a Rg b Rg c R g d Rg

Two identical wires are vibrating in unison If the tension in one of the wires is increased by 2 five beats are produced per second by the two vibrating wires The initial frequency of each wire is 1 02 1 01 1000 Hz A B C D 500 Hz 400 Hz 200 Hz

A plano convex lens has index of refraction n The curved side of the lens has radius of curvature R and rests on a flat glass surface of the same index of refraction with a film of index nfilm between them as shown in Fig 37 18a The lens is illuminated from above by light of wavelength A Show that the dark Newton s rings have radii given approximately by m R n film

Lines of a electrostatic field can t have sudden break in charge free region because A B C D It can t be discontinuous It is imaginary line Gauss s theorem will not be true These line can t exist in charge free region

A solid uniform bar of diameter d and length 1 is hanging vertically from its free end The elongation of the bar due to self weight is a proportional to 1 and inversely prportional to d b proportional to 12 and inversely proportional to d to 1 but independent of di d proportional to 12 but independent of d c proportional

What is the minimum force that needs to be applied on a body of mass 100 g kept on a horizontal surface to set the body in motion Given coefficient of friction between the surface and the body is 0 4 and the force acts parallel to the surface 39200 dyn

a Both sides of a uniform film that has index of refrac tion n and thickness d are in contact with air For normal incidence of light an intensity minimum is observed in the reflected light at and an intensity maximum is observed at A where A A Assuming that no intensity minima are observed between and 2 show that the integer m in Equations 37 16 and 37 17 is given by m A 2 A A b Determine the thickness of the film assuming n 1 40 A 500 nm and A 370 nm

Select incorrect statement regarding mechanical energy of a body system 1 It is sum of kinetic and potential energy 2 It may be conserved even if non conservative force acts on the body system 3 Work done by conservative force is always equal to negative of change in mechanical energy 1 Roth 1 r l

m SolveLancer Test Choose the correct option When an element X undergoes 5 p decays and a decay the daughter nucleus is given by SolveLancer Test n a b c d a b 17 n 44 mz n 5 mx n 4Z n 4 m

Lateral magnification of objective of compound microscope is 100 and angular magnification of its eyepiece is 20 The magnifying power of compound microscope is 1 120 2 5 3 2000 4 1000 ting lons of a terrestrial telescope are 20 cm 10 cm and 0

Review problem A flat piece of glass is held stationary and horizontal above the flat top end of a 10 0 cm long vertical metal rod that has its lower end rigidly fixed The thin film of air between the rod and glass is observed to be bright by reflected light when it is illuminated by light of wavelength 500 nm As the temperature is slowly increased by 25 0 C the film changes from bright to dark and back to bright 200 times What is the coefficient of linear expansion of the metal

A circuit consists of a resistor of 50 a capacitor of 1 F and an ideal self inductor of 0 01H All three are in series with a power supply that generates an EMF of 10 sin cot volt The internal resistance of the power supply is negligibly small The system is at resonance We decreases the frequency of the power supply such that the reactance becomes 592 What will be average power generated by the power supply 1 10 W 2 5 W 3 15 W 4 Zero AVRE

Magnetic flux in Webers linked with a closed circuit of resistance 10 varies with time t in seconds as 5 t 4t 1 The induced emf in the circuit at t 0 2 sec is A 5 mA B 10 mA C 20 mA D 1 A 3

Many cells are transparent and colorless Structures of great interest in biology and medicine can be practically invisible to ordinary microscopy An interference microscope reveals a difference in index of refraction as a shift in inter ference fringes to indicate the size and shape of cell structures The idea is exemplified in the following problem An air wedge is formed between two glass plates in contact along one edge and slightly separated at the oppo site edge When the plates are illuminated with monochro matic light from above the reflected light has 85 dark fringes Calculate the number of dark fringes that appear if water n 1 33 replaces the air between the plates

An insulated box containing a diatomic gas of molar mass M is moving with a velocity v The box is suddenly stopped The resulting change in temperature is 1 3 Mv 2R My 5R 2 4 Mv 3R 2Mv 5R

Internal forces acting in a system of particle can change 1 The kinetic energy but not linear momentum of the system 2 Neither linear momentum nor kinetic energy of the system 3 Both kinetic energy and linear momentum of the system 4 The linear momentum but not the kinetic energy of system

A cube of side a has charge q at two diagonally opposite vertices as shown in the igure The net electric potential at the centre of the cube will be 4q 3 a q 3 a Read More O4q na

A coherent parallel beam of light of wavelength 5000 is incident normally on the plane of slits The slit S is covered with a slab of refractive index 1 5 and thickness t 4 105m as shown The separation between the slits is d 1 mm and the separation between the plane of slits and screen is D 1m Then the position of the central maxima formed on the screen is A 1 cm above point O B 2 cm above point O C 1 cm below point O D 2 cm below point O Hs 1 5 S Lt 4 x 10 m S D 1m scre

An object of mass 2 93 kg moving with an initial velocity of 5 07 i m s collides with and sticks to an object of mass 3 00 kg wi an initial velocity of 3 13 m s Find the final velocity of the composite object 1 m s

mathongo mathongo mathango Amathonge Q9 27 July 2021 Shift 2 The expected graphical representation of the variation of angle of deviation d with angle of incidence i in a prism is mathongo mathonge mathongo mathongo e Wathongs 2 mathongo ago mathongo mothongamathongs mathongo mathongo mathange 3 matho X mathongo X mathongamathongo hongo mathongo X mathongo mothongo ongo mathongo M mathongo mathongo mathongo mathongo mathongo mathongo mathango mathango mathongo mothonge mathongo mathongo 79 mathongo mothongo mathango mathonge mothongo mathongo mathongo mathongo Pothongo mathongemathongo mathongo mothongemathongo mathongo mathongo mathongo mathongo

In a Young s double slit experiment using light of wave length a thin piece of Plexiglas having index of refrac tion n covers one of the slits If the center point on the screen is a dark spot instead of a bright spot what is the minimum thickness of the Plexiglas

mathongo mathongo A ray of light passing through a prism suffers minimum deviation It is found that the hongo mathor mahongo mathor angle of incidence is double the angle of refraction mathongo mathongo within the prism Then the angle of prism is mathongo mathor in degrees

point Two capacitors C 4 F and C 7 F are connected across a 40 V battery The battery is removed and plates of opposite sign are connected Find the final charge and potential ference for each capacitor 1 C

Q7 25 July 2021 Shift 2 A ray of light entering from air into a denser medium of refractive index as shown in figure The light ray suffers total internal reflection at the adjacent surface as shown The maximum value of angle should be equal to mathongo So mathongo 1 17 1 sin 2 sin 3 sin 4 1 5 mathongo mathongo mathonge 4 ma3ge mathongo Wmathongo mathongo magmathongo mothongo mathoniga mathongo mathanga mathongo mathongo mathongo mathongo mathongo mathonga mathanga mothongo mothongs mathongo mothongo mathongs mathongs mathongo mathongo mathongamathanga mathonga mathongo

41 In the indicator diay am shown for an ideal gas the heat exchange between the gas and surrounding is zero for process OA The heat exchange will be negative for the process P O 1 B 3 D D B Ai 2 C 4 Both C and D

111 If E G and K denote the young s modulus modulus of rigidity and bulk modulus for an elastic material then which one of the followings can be possibly true a G 2K c K E b G E d G K E Engg Services 205

A beam of unpolarized light of intensity lo is passed through a polaroid A and then through another polaroid B which is oriented so that its principal plane makes an angle of 45 relative to that of A The intensity of the emergent light is A Io 8 B Io C Io 2 D I0 4

Identify the correct statement O A neutron is formed by an electron and a proton combining together Therefore it is neutral Mass of an electron is about 1840 times that of proton O Each energy level in an atom is associated with a fixed amount of energy 14 and 14N shows different 7 chemical reactivity due to difference 6

Acceleration a of a particle moving in a straight line varies with its velocity v in m s as a 2 2 v m s Find the maximum possible speed of the particle assuming at f 0 particle was at rest

4 Relative error 8 The dimensions of solar constant energy falling on earth per second per unit area are 1 MOLOTO 3 ML T 2 MLT 4 MT

A bimetallic strip made of steel and brass each of thickness 2 8 mm heated through 200 C abrass 19x10 6 C a steel 1 It bends with concave side steel rod II IT bends with convex side steel rod III It radius of curvature 2m on convex side brass IV Expansion of steel is greater than brass A I and III B I and II C III and IV D I II and IV 12x10 6 C Then

One radio transmitter A operating at 60 0 MHz is 10 0 m from another similar transmitter B that is 180 out of phase with A How far must an observer move from A toward B along the line connecting A and B to reach the nearest point where the two beams are in phase

45 A physical quantity P is given by the relation If t denotes the time the dimensions P P of constant a are 1 T 3 IT 1 2 1 4 T

9 The amount of heat energy Q used to heat up a substance depends on its mass m its specific heat capacity s and the change in temperature AT of the substance Using dimensional method find the expression for s is Given that s L T K is 1 QmaT Qm 2 Q MAT m