Physics Questions

21 Arod of length 2m is at temperature of 20 C The temperature is increased to 50 C If permitted expansion without thermal stress is 0 4mm the thermal stress produced is Y 2 10 Pa a 15 10 C 1 5 x 107 N m 2 4 107 N m 3 3 x 107 N m 4 2 107 N m

A charged particle q is shot towards another charged particle Q which is fixed with a speed u It approaches Q upto a closest distance r and then returns If q is shot with speed 2u the closest distance of approach would be 3 2r 4 r 0 2 r 2

Q17 The angular velocity of a body changes from one revolution per 25 seconds to one revolution per seconds without applying any torque The ratio of its radius of gyration in two cases is 25 d 25 1 O A OB C O D O Other a 5 1 b 1 5 c 1 1 po

A closed surface with two parallel bases is completely immersed in a uniform electric field 5 0x10 N C as shown in figure Find the electric flux through the surfaces 1 S 2 S 3 Sa Y cm 2015 105 10 15 20

A force is applied on a rod of mass M and lenght L at a distance of L 4 from the hinge point then calculate the force is exerted by the hinge on the rod in order to keep the rod in equilibrium L 4 1 Mg upwards 2 Mg downwards 3 2 5 Mg upwards 4 1 5 Mg downwards

SolveLancer Test When an object projected vertically up from top of the building then its average velocity is 10 m s and it took 4 sec to reach the ground Find the difference between average speed and magnitude of average velocity SolveLancer Test a 1 5 m s b 2 5 m s c 2 m s d 5 m s

A car moving with a velocity of 10 m s can be stopped by the application of a constant force Fin a distance of 20m If the velocity of the car is 30 m s It can be stopped by this force in 120m 3 3 60 m 1 2 20 m 4 180 m

4 None of the above The maximum electric field at a point on the axis of a 36 uniformly charged ring is E At how many points on the axis will the magnitude of electric field be E2 1 1 2 2 3 3 4 4 4 340 fait for an E 2 1 I fa fa 2 2 3 3 en f 4 4

A long wire having linear charge density is moving with constant velocity v along its length At an instant a point charge is at a distance r from the wire and is moving with same speed in opposite direction The net force acting on the charge is given by OD 1 A Hou2 q 2 r EO bjuda q C UMO 0 1 0 4 0 19 do ead 2 r Eo B auiba 19m bus D q 2 ro 1 zero bono lo beib 2 0413 r q

A particle moves with simple harmonic motion in a straight line In first ts after starting from rest it trave a distance a and in next ts it travels 2a in same direction then 1 amplitude of motion is 4a 3 amplitude of motion is 3a 2 time period of oscillations is 6t 4 time period of oscillations is 8t

Two metal spheres of capacitance C and C carry same charges They are put in contact and then separated the final charges Q and Q on them will satisfy 1 3 ala ala ala V II A Q els ls l

3 f 12 cm 4 f 12 cm A beam of light is converging towards a point I on 9 a screen A plane glass plate whose thickness in the direction of the beam 1 refractive index is introduced in the path of the beam The convergence point is shifted by 1 1 away 2 1 1 1 3 t 1 2 4 1 away nearer nearer 3 f 12 cm 4 f 12 cm fur fare face 1 x furuka for r H fax garran at efter for freunfo 1 1 1 1 2 Telegram nequestionpaper 3 1 1 1 4 1 1 1 18 are en

A body cools from 80 C to 70 C in 5 mins What wil be its temperature in the next 5 mins Temperature of surroundings is 10 C 7 kan 2 1 60 C 2 63 32 C alt 3 61 43 C 4 65 C 10 2K 75 10

Graph Electronegativity Y axis vs Atomic number X axis and analyze the patterns observed for elements 1 to 20 then examine your graph Find atomic numbers 3 11 and 19 that correspond to the elements in Group 1 What happens to the electronegativity value as you move down the group Explain this trend using a Bohr Rutherford diagram and the concept of radius

A staircase consists of five steps each 20 cm high and 20 cm wide If horizontal velocity of a ball is sufficient to fall it from top stair to bottom stair directly then the time taken by the ball to reach at bottom stair will be nearly 1 0 2 s 2 0 3 s 3 0 45 s 4 0 8 s In 0 1 If hall hits the edge of bottom stair then

A ray of light is travelling in air falls on a transparent glass slab of refractive index3 If the refracted rays and reflected rays are mutually perpendicular What is angle of incidence 30 45 60 53

Q5 A car is moving along a horizontal curve of radius 20 m and coefficient of friction between the road and wheels of the car is 0 25 If acceleration due to gravity is 9 8 m s2 then its maximum speed is b 5 m s c 7 m s d 9 m s a 3 m s O A OB O C O D O Other 1 po

The Lagrangian of a particle of mass m moving in a plane is given by L 1 2 m v a xv yv where v and v are velocity components and a is a constant The canonical momenta of the particle are given by y a p mv and p mv my c P mv ay and p mv ax 6 p mv ay and p mv ax d p mv ay and p mv ax

A layer of oil 3 cm thick is floating on a layer of coloured 5 water 5 cm thick Refractive index of coloured water is 3 36 and apparent depth of two liquids appears to be 7 What is refractive index of oil O 1 2 O 1 3 O 1 4 1 52 cm

Figure shows a particle of charge q and mass m moving with velocity v along the x axis enters a region of uniform magnetic field Minimum value of v so that the charge q is deflected by an angle 30 is a M M M b B X

In an n p n transistor circuit the collector current is 10 mA If 90 of the electrons emitted reach the collector 1992 2M a the emitter current will be 9 mA b the emitter current will be 11mA c the base current will be 1mA d the base current will be 1 mA

A constant force F is applied on the rod of mass M and length L placed between two conducting fixed rails in a uniform magnetic field A capacitor C is connected between the two rails as shown in the diagram Neglecting the resistance of the rod and the rails which of the following statement is incorrect 1 Question Type Single Correct Type 2 F 3 M L Acceleration of rod is constant Current in the wire is constant and nonzero Charge on the capacitor is constant

Two events are separated by a distance of 6 x 105 km and the first event occurs 1 sec before the second event The interval between the two events a is time like c is space like b is light like null d cannot be determined from the information given

If linear charge density of a wire of length L 37 af fx ata X depends on distance x from one end as Ap x Find total charge of wire A 1 AL 3 AL 2 AOL L 4 none of these of a thin disc having 38 at an A Xo x L 1 AL 3 AL Rent a SER qrafia 2 AL 4

2 20 Four capacitors each of 1 F are joined as shown in figure The equivalent capacitance between the points A and B is A C C C HH C B

A person wears eye glasses with power of 5 5 D for distance viewing His doctor prescribes a remedy of 1 5 D for his near vision What should be the focal length of extra lens which should be pasted over lower section of his eyeglasses for correct near vision 12 5 cm 14 3 cm 16 7 cm 19 3 cm

A converging lens of focal length 50 cm is placed co axially in contact with another lens of unknown focal length If the combination behaves like a diverging lens of focal length 50 cm What is power of second lens 2 D 2 D 4 D 4 D

46 A block of mass 3m is connected with a string which is wound on pulley of mass m and radius R as shown in the figure If the system is released from rest Then acceleration of the block will be consider pulley as uniform disc 1 g 3 6g 7 3m 2 4 5g g 3

ALLEI Three charges Q q and q are placed at the 32 vertices of an equilateral triangle of side as shown in the figure If the net electrostatic energy of the system is zero then Q is equal to 1 2 2 q q q

The velocity of the car is expressed as V x 4x 3 3 and its time as t x 2x 5 Create a function model about the distance travelled of the car To solve the problem follow these steps a State the function model representing the velocity of the car b State the function model expressing the time lapse of the car c Recall the formula in finding the velocity of a moving object with respect to distance and time Derived a formula of distance from that formula d Create the function model for the distance travelled by the car Simply state your answer in a more comprehensible function model

Three concentric spherical shells have r adii a b and c a b e and have surface charge densities and o respectively If V Vn and Vc denote the potentials of the three shells then for c a b We have

A V tube of uniform cross sectional area A is filled with a liquid of density p as shown in figure Each arm has length 1 and inclined to vertical at an angle a If the free surface of the liquid in one arm is disturbed by displacing it a depth x below the equilibrium configuration determine the frequency of oscillation a A c 2 1 1 2 g cos a A 1 g cosa X X b a 1 2 V d 2 B B g cos a 1 sa g cos c

the lengths of the 13 In Fig 11 24 two bars of the same metal are connected The length of the first bar is half of that of the second but the cross sectional area is double What is the temperature of the junction of the bars Ans 20 C 25 C 0 C

Two balle A 2kg and B 4kg move towards each other and after collisio n moves backward If the initial velo cities of A and B were 2m s and 4m s respectively then what could be the ir respective final velocities

In case of a prism red light bends the le ast whereas in the case case of raindro p red light will have greater angle of dev iation i e after refraction partial internal reflect and reflect inside the raindrop Am I right

Three charges q 1 x 10 C q 2x 10 C 28 and q 3 x 10 C have been placed as shown in figure Then the net electric flux will be maximum for the surface S S A 1 S 2 S 3 Sy 4 Same for all three 14 9 1x 3 question 1 S 2 S 3 S 4

Tyndall effect is observed when 1 Diameter of dispersed particles is not much smaller than the wavelength of light used ii The refractive indices of the dispersed phase and dispersion medium differ greatly in magnitude iii Diameter of dispersed particles is much larger than the wavelength of the light used 1 i and ii 2 i and iii 3 ii and iii 4 i ii and iii

ALLEN The focal lengths of the objective and eye piece 7 of a telescope are respectively 100 cm and 2 cm The moon subtends an angle of 0 5 at the eye If it is looked through the telescope the angle subtended by the moon s image for normal adjustment will be 1 100 3 25 2 50 4 10 A shortsighted person can read a book clearly at faut 100 cm TARINA 1 100 3 25 fuge aun aften of die strat 2 5 gr ff ren an at af 2 50 4 10 Uffe fe ad vta 10 cm

A single phase full bridge inverter bed from 230V DC is connected to load R 10 Q L 0 03 H The inverter is operating in 180 square wave mode The RMS value of fundamental component of output voltage is A 207 10 V C 217 10 V B 407 10 V D 237 10 V

Topic Electrostatic from Suspended Ball System To problems based On Conservation of Mechanical Energy Gravitation From Gravitational Potential Energy to Problem Based On Kepler s Law A convex mirror of focal length f forms an image 1 and and are fafara R which is times the object The distance of the n real object from the mirror is 1 1 n 1 f n 1 1 f 2 a cri 1 n 1 f CTX n 1 n Ja arafa af 2 n IC

4 The air bubble cannot form a real image A bi convex lens is formed with two 5 thin plano convex lenses as shown in the figure Refractive index n of the first lens is 1 5 and that of the second lens is 1 2 Both the curved surface area of the same radius of curvature R 14 cm For this bi convex lens for an object distance of 40cm the image distance will be n 1 5 1 280 0 cm 3 21 5 cm R 14cm n 1 2 2 40 0 cm 4 13 5 cm 4 gegen af fafara anar en fax fax for 1 1 2 R 14 cm falfa 40 cm fe fafara X n 1 5 Telegram question paper 1 280 0 cm 3 21 5 cm R 14cm an n 1 2 2 40 0 cm 4 13 5 cm

For the given ac circuit source voltage is given by V 77 100 sin 10t 2 where V is in volt and t is in second 1 2 R 10 39 www Question Type Single Correct Type 3 L 1H 000000 ac source Power factor of the given circuit is 2 Current as a function of time t is given by i A 5 sin 10t 2 Voltage across resistor as a function of time 75

ALLEN An air bubble is inside water The refractive 4 index of water is 4 3 At what distance from the air bubble should a point object be placed so as to form a real image at the same distance from the bubble 1 2R 2 3R 3 4R 4 The air bubble cannot form a real image gegen utan ada 4 3 18 aggage cu va face and then af fffa fafara gera 1 2R 2 3R 3 4R 4 gergea anafafafara

Classr u m us Posi Velo dis B Answer time Rep at t 0 particle is atzero and slope dec becomes 0 and then ve Z Posi rep let us take particle at at een position zero the particle would either have a tve ora ve velo but not zero at t 0 particle has tve Velo rep time at 0 slope of d DT graphiszero the slope initially increases but then decreases at 0 particle is at rest Speed 0

Figure shows the electric lines of force emerging 25 from a charged body If the electric field at A and Bare E and E respectively and if the displacement between A and B is r then 1 E E 2 E E 3 EX 4 E Enthusiast Course Il E H 29072020 r Legen Space for Rough Work fax saftra fuus frent arch tya ara rand front mi ti fa Berta 2 EE 3 EA 4 EA r 1001CMD302220005 Page 9 52

A prism having an apex angle 4 and refraction 3 index 1 5 is located in front of a vertical plane mirror as shown in figure Through what total angle is the ray deviated after reflection from the mirror 1 176 3 178 90 2 4 4 2 er a cada farger f ffer 1 176 3 178 41 5 1 arx fena una 90 2 4 4 2

2 A plano convex thin lens of focal length 10cm is 12 silvered at its plane surface The distance d at which an object must be kept in order to get its image on itself is 2 20cm 4 2 5cm 10 T A Z unde ve u u af fr f fated and deg Telegram ne questionpaper 1 Sem 3 10cm 3 A body of mass m is situated at distance 4R 13 1 5cm 3 10cm 2 20cm 4 2 5cm mayat 4R

irection ater in 3 in 1 1 city of A 1 24 J 2 48 J 3 56 J 4 64 J A block of mass 5 kg is placed on rough horizontal surface of 0 5 An external force F 50 N is acting on it at an angle of 37 above the horizontal The work done against friction when block cover 10 m distance along horizontal is 1 100 J 3 400 J 2 200 J 4 500 J

3 4 n 1 The speed of light in media M and M is 1 5 10 m s 2 and 2 0 x 10 m s respectively A ray of light enters from medium M to M at an incidence angle i If the ray suffers total internal reflection the value of iis 1 Equal to or less than sin 2 greater than sin 3 Less than sin 4 Equal to sin cilm cilm 35 3 1 5 10 m s 320 10 ms M M 2 SINH N TH NH NHAU I g i Se HAB 2 sin 2 sefires H 1 sin sin stionplay 4 sin 2 3 4 n 1 f CLICK H apert

A common emitter amplifier circuit built using an n p n transistor is shown in the figure Its DC current gain is 250 Rc 1k2 and Vcc 10V What is the minimum base current for VCE to reach saturation Main 2019 8 April II Ve RB cl Rc Vcc