Physics Questions

In the given diagram if the spring connecting D and C is cut then what will be the accelerations of blocks A B C D at that instant 1111 0000 0000 4kg C3kg B2kg 0000 A 1kg

A particle is projected from ground at an angle 8 At a certain instant the velocity vector y of particle makes an angle a with horizontal g modulus of V dt gsina Tangential acceleration has magnitude of g sin a Normal radial acceleration g cos a

18 A thin uniform rod of mass M 0 112 kg and length L 0 096 m is suspended by a wire that passes through its center and is perpendicular to its length The wire is twisted and the rod set oscillating The period is found to be 2 14 sec When a flat body in the shape of an equilateral triangle is suspended similarly through its center of mass the period is found to be 5 83 sec Find the rotational inertia of the triangle about this axis

4 If x v and a are displacement velocity and the acceleration respectively of a particle executing SHM of fixed time period T then which of the following remains constant with time 1 a T 3 T 2nv eraf 2 4 aT X aT LTD 2 LT 37

In the circult shown the power factor of the circuit is 1 power factor of box is 4 5 source voltage is 100V angular K Henry then find frequency 100 rad sec and current flowing in circuit is 5 amp Value of inductance of inductor is 20 value of K A 5 Amp Box 100 V 100 rad sec

39 40 in further 10 minutes it will cool from 38 C to A 36 C 8 36 4 C C 37 C The temperature of the body in C denoted by the variation of versus time t is best denoted as A C 40 C AC 8 D a C 10 D 37 5 C When the body temperature has reached 38 C it is heated again so that it reaches to 40 C in 10 minutes The total heat required from a heater by the body is

76 In Young s double slit experiment two slit are d distance apart Interference pattern is observed or screen at a distance D from the plane of slit A bright is observed on the screen directly opposite to one of the slits The wavelength of light is 1 3 D 2d D 2 d 2D d

The remote control of a TV emits infra red light of wavelength 900 nm The TV detector is made of a semiconductor whose band gap is x eV The detector is shielded by a semiconductor optical filter whose band gap is y eV From the four options below select the best option for the TV to function 0x 2 0 and y 1 2 2 2 and y 1 0 X P 8341837 441837 4

E A particle of mass m having a charge Q enters into a circular region of uniform magnetic field of radius R with velocity v directed towards the centre The direction of the magnetic field is inwards Then the deviation in the path of the particle will be 1 2 tan 1 BqR mv 3 tan 1BqR mv 2 0 3qR 3 5B field of the contro of a current carrying circular coil of radius R and B is the 4 tan 1

A uniform rod of mass m and length is hinged at one end which is released from the position shown in the diagram from rest Rod is free to move in vertical plane when rod becomes horizontal then 0 0 Acceleration of COM of rod is 3g sin 0 2 Acceleration of COM of rod is Force applied by hinge on rod is 3mg sin 6 mg 2 3919 3g cos 0 2 9 Force applied by hinge on rod is 3mg cos 0 3mg 2 4 YA X

A radar sends slow moving a signal of frequency 8 x 10 Hz towards an aircraft approaching the radar If the reflected wave shows frequency shift 2 10 Hz the speed with which the aircraft is approaching the radar is velocity of radar signal is 3 x 108 m s 1 37 5 m s 3 4 m s 2 75 m s 4 85 m s

block of mass m is placed on wedge mass m shown in fig Find out magnitude of force F such that block m remain stationary w r t wedge All surfaces are frictionless and acceleration due to gravity is g m m

Assuming that gravitational potential energy at the surface of earth is zero the change in gravitational potential energy of an object of mass m when taken to a height h from the surface of earth of radius R mass M is given by h R A B C D GMm R h GMm R h mgh mghR R h

The 18 Two balls are dropped from the same at two different places A and B where the and SB acceleration due to gravities are ga body at B takes t seconds less to reach the ground and strikes the ground with a velocity greater than at A by v m s Then the value of v t is 1 3 1 SASB 1 SASB 2 2 SASB 4 SASB

A uniform rod AB is placed which makes an angle with the floor Now end point B of rod is pulled with a horizontal velocity 10 m s as shown Taking the length of the rod as the velocity of CM of the rod At the instant when 53 is AAAAAAAAAAAA e B A 12 5 m sec 25 4 C 6 m sec A 10m s m sec D 25 m sec

Q 29 A force of 21 73 Newton is applied to a body of 5 kg mass for 10 seconds The initial velocity of body is 23 m sec Find the value of final momentum of body f 2 fj m 5kg 10 11 21 A 25 kg m sec B 60 kg m sec C 85 kg m sec D 65 kg m sec Q

one end which is released from the position shown in the diagram from rest Rod is free to move in vertical plane when rod becomes horizontal then y 0 Acceleration of COM of rod is Force applied by hinge 3mg sin 0 mg mi 2 Acceleration of COM of rod is 3g sin 3g 2 on rod is 3g cos 0 2 1 1 1 Force applied by hinge on rod is 3mg cos 3mg

ed ly 57 A beam of light strikes a piece of glass at an angle of incidence 60 and the refracted beam is completely Beetquestionane polarised The refractive index of the glass is 1 1 5 3 2 nd d 2 3 4 312

5 In an electron microscope if the potential is increased from 20 KV to 80 KV the resolving power of the microscope will change from R to 1 R 3 2R 2 4R 4 2

E D 18 A parallel beam of mono chromatic light o wavelength 5000 A is incident normally on a single narrow slit of width 0 001 mm The light is focused by a convex lens on a screen placed on the foca plane The first minimum will be formed for the angle of diffraction equal to 1 30 3 15 2 60 4 0

In the given AC circuit current and potential difference across the resistance inductor and capacitor are shown in figure Then which of the following options is are correct 1A R 50 V 20 Volt V 30 Volt www HH current leads the voltage in phase B Voltage leads the current in phase RI Power factor of the circuit is Applied voltage is 15 V 1

Axniform solid cylinder of mass m and radi2R rests on a horizontal table A string attached to it passes over a pulley disc of mass m and radius R that is mounted on a fricitonaless axle through its centre A block of mass m is suspended from the free end of the spring The string does not slip over the pulley surface and the cylinder rolls without slipping on the table Om

2 15 A circular coil A has a radius R and current flowing through it is I Another circular coil B has a radius 2R and if 21 is the current flowing through it then the magnetic fields at the centre of the circular coil are in the ratio i e BA to BB of a 4 1 b 2 1 c 3 1 d 1 1

A bob of a simple pendulum executing SHM in air has time period To and in water has time period T If density of bob is 4 3 103 kg m then correct relation between T and To is Neglect friction 0 4 T T 3 T 2T T 2 T 2 4 T 4T

In figure shown a boat can move with 10 m s in still water If it steers as shown then it will reach other shore To reach at point B it can B O move at the same angle without changing speed move with same speed with greater angle move with greater speed at same angle move with greater speed at greater angle 800m 10 37 8 m s

A block A of mass m is slipping down with constant speed on a rough wedge B of mass M kept at rest on a table as shown in figure Then B A Friction force on wedge due to table is zero B Friction force on wedge due to table towards left C Contact force on wedge due to table is greater than m M g D Contact force on wedge due to table is making non zero angle with vertical

5 A particle of mass m is executing oscillation about the origin on the x axis Its potential energy is U x Klx13 where K is a positive constant If the amplitude of oscillations is a then its time period Tis 1 Droportional to a 3 2 Proportional to a 2 Proportional to

Q 43 Option 1 9PoVo An R Option 2 3PoVo 2n R Option 3 9PoVo 2n R Option 4 9PoVo nR n moles of an ideal gas undergoes a process A B as shown in the figure The maximum temperature of the gas during the process will be 2Po Po A B Vo 2Vo V

In young s double slit experiment the y co ordinates of central maxima and 10th maxima are 2cm and 5cm respectively When the YDSE apparatus is immersed in a liquid of refractive index 1 5 the corresponding y co ordinates will be 1 2cm 7 5cm 3 3cm 6cm 2 2cm 4cm 4 3cm 7 5cm

A photoelectric surface is illuminated successively 2 2 by monochromatic light of wavelength 2 and the maximum kinetic energy of the emitted photoelectrons in the second case is 3 times that in the first case the work function of the surface of the material is h Planck s constant c speed of light Re AIPMT 2015 1 3 hc 32 hc a 2 4 hc 22 CAU 2hc If

A progressive wave is represented by y 12 sin 5t 4x cm On this wave how far away are the two points having phase difference MHT CET 2016 of 90 A EN RO cm cm 2010 B D T cm 4 T 16 cm 0

Three long straight wires A B and C are carrying currents as shown in the figure The resultant force on B is directed A B C IAT 2A 3A d d 1 towards A 2 towards C 3 perpendicular to the plane of paper and inward 4 perpendicular to the plane of paper and outward

man walking downhill with velocity u finds that his umbrella gives him maximum protection from rain when he holds it such that the stick is perpendicular to the hill surface When the ma ns back and climbs the hill with velocity u he find that it is most appropriate to hold the umbrella stick vertical Find the speed of raindrops w r t ground The inclination of the hill is 0 30 52 m s 0 30

The figure shows two points source which emit light of wavelength in phase with each other and ar at a distance d 5 52 apart along a line which is perpendicular to a large screen at a distance L from t cente of the source Assume that d is much less than L Which of the following statement s is are correct excluding fringe at infinity B C S L Screen Ty 0 0 Only Only six bright fringes appear on the screen Point y 0 corresponds to bright fringe five bright fringes appear on the screen Point y 0 corresponds to dark fringe

Column I A The force exerted by X on Y has a magnitude Mg B The gravitational potential energy of X is continuously increasing C Mechanical energy of the system X Y is continuously decreasing D The torque of the weight of Y about point P is zero P X Y Column II p Block Y of mass M left on a fixed inclined plane X slides on it with a constant velocity q Two ring magnets Y and Z each of mass M are kept in frictionless vertical plastic stand so that they repel each other Y rests on the base X and Z hangs in air in equilibrium P is the topmost point of the stand on the common axis of the two rings The whole system is in a lift that is going up with a constant velocity r A pulley Y of mass mo is fixed to a table through a clamp X A block of mass M hangs from a string that goes over the pulley and is fixed at point P of the table The whole system is kept in a lift that is going down with a constant velocity s A sphere Y of mass M is put in a non viscous liquid X kept in a container at rest The sphere is released and it moves down in the liquid A sphere Y of mass M is falling with its terminal

21 An a particle moves in a circular path of radius 0 83 cm in the presence of a magnetic field of 0 25 Wb m The de Broglie wavelength associated with the particle will be AIPMT Prelims 2012 1 10 A 3 1 2 0 01 A 4 0 1 A

Between two coherent waves phase difference at a particular position is 1 A6 x A6 t 2 A t constant 3 Ap x A6 t constant

Two identical thin lenses are kept one beside other or optical axis as shown in the figure The right surface right lens is silvered focal length each lense is 20 radius of the silvered surface is 2 cm the focal leng combined system is Consider

n Find the resistance across AB From figure it is clear that terminal A and point 2 are common point and terminal B and po are common point so redrawing the diagram we have 60 A Rp 2 5 3 2 10 22 www 1592 Now 62 102 and 15 are in parallel so effective resistance is 1 1 6 10 15 B

An elevator is moving upward with a constant speed of 10 m s A man standing in the elevator drops a coin from a height of 2 5 m from floor of elevator The coin reaches the floor of the elevator after a time sec t 2 What is the value of t

A thin rod of mass m and length is hinged to a ceiling and it is free to rotate in a vertical plane A particle of mass m moving with speed v strikes it as shown in the figure and gets stick with the rod 2 60 m The value of v for which rod becomes horizontal after collision is Im 168 9 gl The value of v for which rod becomes horizontal after collision is 53 3 ge Angular momentum of rod particle system will remain constant about hinge just before and after collision Angular momentum of rod particle system will remain same about centre of mass just before and after collision

Boy A B and C are moving with constant velocities as shown in diagram A VPQ 5 m s 5 2 m s VAB 51 VBC 51 101 VCA 51 51 VCE 5 10 45 B it shows velocity of P w r t Q C 5 m s L Ay X

34 A plane mirror rotating at an angular velocity 4 radian s reflects a light beam The angular velocity of the reflected beam is 1 2 rad s 3 8 rad s 2 6 rad s 4 4 rad s

A rigid ball of mass m strikes a rigid wall at 60 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 a mV mV c 2 b 2 mV mV d 3 NET V 60 60 www

A town is getting 800 kW electric supply from a step down transformer at 400 volt Turn Ratio 10 1 The electricity is supplied from H T Line from a power plant generating 400 volt AC The A C is step up at plant to reduce line losses and then it is transmitted by H T line of total resistance 20 Q Find configuration of step up transformer A B 500 7000 volt D 600 9000 volt C 400 8000 volt 700 3000 volt

hy not possible to use equation of v like 2gh 1 k2 r2 2 4 AN OSCillatory motion 15 9 A solid cylinder begins to rolls down on 30 incline of length 9 m without slipping The speed of centre of mass at the bottom of plane is 1 3g 2 g 3 2 g 2 4 6g B The pres where F drawn o of initial tank will 11P 11

In figure a hollow tube of mass M is free in horizontal direction The system is released from rest There is no friction present The tube and blocks are taken as system i Momentum of the system is conserved in x direction ii Speed of A w r t M speed of B w r t M iii Acceleration of centre of mass along X axis is constant iv Centre of mass has finite acceleration Evaluate the above statements and choose the correct option from the following m A M 723 B A Statements i ii are true and iii iv are false B Statements i ii are false and iii iv are true

53 When a YDSE is performed using a monochromatic source of light fringe width is found to be 1 2 mm The minimum distance above central maxima at which 60 intensity is th of the maximum value is 1 0 1 mm 3 0 3 mm 2 0 2 mm 4 0 4 mm

15 Two coherent waves of intensities I and 41 superpose then the maximum and minimum intensities produced are 1 51 and 31 3 91 and 31 2 91 and I 4 51 and 1

A uniform rod of mass M and length L is suspended by two smooth hinges 1 and 2 as shown in the figure A force F is applied downward at a distance from the hinge 2 Due to the application of force F the hinge 2 breaks At this instant applied force F is also removed The rod starts to rotate downward about hinge 1 g 10 m s2 Choose the correct statement s F The reaction at hinge 1 before hinge 2 breaks is M L The reaction at hinge 2 before hinge 2 breaks is 2F 3 O The reaction at hinge 1 just after breaking of hinge 2 is zero The reaction at hinge 1 just after breaking of hinge 2 is