Physics Questions

In the shown arrangement particle at C connected by the help of two ideal strings is moving with minimum possible speed in form of conical pendulum as shown maintaining the configuration Find angular velocity of its revolution 0 2 m B 60 10 3 rad s 10 rad s 20 rad s 20 3 rad s C

8 A block of mass 10kg is initially at rest on a horizontal rough surface At a time t 0 a time dependent force F acts on it horizontally as shown in the figure Force F stops acting at t 7 seconds Consider that coefficient of static and kinetic friction both are equal to 0 5 and g 10 ms 2 10kg F N 100 40 I 1 7 t s 1 mv2 2 30 110x60x60 a Maximum kinetic energy acquired by the block is 125 J b Maximum kinetic energy acquired by the block is 50 J c Total time for which the block is moving with non zero velocity is 5 4 s d Total time for which the block is moving with non zero velocity is 7 4 s

A body moves from x 1 to x 4 and then to x 4 Which of the following is correct 1 Its displacement is zero 2 The distance covered by it is 5 units 3 Its displacement is 3 4 Distance covered by it is 9 units

Single Correct A If mass M time T and energy E are taken to be fundamental quantity then dimensional formula for length is ME T B EM 21 2 E M 1 2T EZM 1 2T P

Why not linear momentum since acc to Newton first law without external forces momentum does not change Q11 Internal forces can change for a system rakas ara ukalda Por faz ar A Kinetic energy but not linear momentum in an and B Linear momentum but not kinetic energy nu erau an afde m u vai n Linear momentum as well as kinetic energy 3 D Neither kinetic energy nor linear momentum Answer

NEET Full Course Material Two cells of emfs E and E E E are connected as shown in figure a 3 1 2 3 When a potentiometer is connected between A and B then the balancing length of the potentiometer wire is 300 cm On connecting the same potentiometer between A and C the A E balancing length is 100 cm The ratio potentiometer experimar tion when a B b 1 3 d 3 2 E HTC E is E

It s for a test Problem A sine wave travels in the positive x direction It has an amplitude of 1 50 cm a speed of 300 m s and a frequency of 200 Hz Determine the angular number of waves

The length of vibrating string is 75 mm and fundamental frequency of vibration is 530 Hz The load applied to string is 1 kg hence mass per unit length of string is CO3 O 0 0155 g cm 1 55 kg cm O 0 155 kg cm O 1 55 g cm

Find the capacitance of a multiple plate capacitor made from 30 pairs of 10x15mm rectangular plates separated by 50nm of polystyrene k 2 6 If a 4uF capacitor is connected to a constant current source therefore its current is given in the equation ic t 10mA Determine the voltage power and energy at 2ms

Q4 You are being given the following two spherical surfaces 3 a Denser Convex Spherical surface for the propagation of the light rays from rarer Air to denser medium b Denser Concave Spherical surface for the propagation of the light rays from denser medium to Rarer Air If you join above two equations for the combination of a and b what would you get

A wedge of mass M is pushed with an constant acceleration of a gtan along a smooth horizontal surface and a block of mass m is projected down the smooth incline of the wedge with a velocity V relative to the wedge M m A The time taken by the block to cover distance L on the incline plane is B The time taken by the block to cover distance L on the incline plane is C The normal reaction between the block and wedge is mg sect D The horizontal force applied on the wedge to produce acceleration a is M m g tano COMPREHENSION 2L gsine

d If the fish is stored at ordinary temperatu 10 Three identical buckets were filled with water to the brim In the first one a solid iron ball about the size of a football was dropped In the second bucket a cricket ball and in the third one five glass marbles were dropped In each case some water was spilled The order of the volume of water that spilled is a First bucket Second bucket Third bucket b c d Third bucket Second bucket First bucket Second bucket Third bucket First bucket First bucket Third bucket Second bucket the beginning of civiliza

A football of radius R is kept on a hole of radius r r R made on a plank kept horizontally One end of the plank is now lifted so that it gets tilted making an angle 9 from the horizontal as shown in the figure below The maximum value of 0 so that the football does not start rolling down the plank satisfies figure is schematic and not drawn to scale A sino R Plank B tane 2r R 0 C sino T 2R D cose 2R

gure shows a particle of charge q and mass m moving with velocity v along the x axis enters a gion of uniform magnetic field Minimum value of v so that the charge q is deflected by an angle 30

A pendulum is hanging from the ceiling of a If the cage moves up with constant acceleration a its tension is T and if it moves down with same acceleration the corresponding tension is T 2 The tension in the string if the cage moves horizontally with same acceleration a is AS C 44442 T T T 2 T T 2 a T B D T a T T2 2 T T2 2

Three consecutive resonant frequencies of stretched string fixed at both ends are 60 Hz 90 Hz and 120 Hz then NCERT Pg 382 1 The fundamental frequency is 30 Hz 2 The given frequencies are 1st 3rd and 5th harmonic 3 The given frequencies are 1st 2nd and 3rd overtone 4 Both 1 and 3 are correct

Question No 11 Single Correct A A A river is flowing from east to west at a speed of 6m min A man on south bank of river capable of swimming 12m min in still water swim across the river in the shortest time he should swim A B D due north due north east due north east with double the speed of river none of the above

1g of water as 100 C occupies a volume 1670cm when it becomes steam at 100 C at one atm The change in internal energy for the process is nearly take L 540 cal g p 1g cc latm 10 N m steam water 1 40 cal 2 540 cal 3 500cal 4 580 cal

Maximum kinetic energy of emitted electron depends on frequency of incident photon when frequency of incident photons is Equal to threshold frequency Half of threshold frequency Greater than threshold frequency One third of threshold frequency

A few electric field lines for a system of two charges Q and Q fixed at two different points on the x axis are shown in the figure These lines suggest that a Q Q l b Q Q c at a finite distance to the left of Q the electric field is zero d Q Q Q

Two plates of same mass are attached rigidly to the two ends of a spring One of the plates rests on a horizontal surface and the other results a compression X of the spring when it is in steady state To lift off the lowest plate after removing the force What further compression is required 1 0 5X 2 3X ITTT T 600000000 m

7 Find the compression in the spring if the system shown below is in equilibrium 1 3 0 mg m mg cos 0 k M k voor 2 pmm Smooth mg sin cose k 4 Zero

4 ppm means 4atoms per 10 6 atoms then ne 4 10 27 4 10 6 only na why they are giving like this please explain A pure semiconductor crystal has 4 x 1027 atoms m It is doped by 4 ppm concentration of pentavalent atom The number of holes per m will be n 10 6 m 10 1 m 3 10 m 3 10 m 3 108 m 3 Solution

A uniform round object of mass M and radius R is placed on a rough plank of mass M which is placed on smooth surface Round object is given velocity vo towards right and it starts perfect rolling on plank after some time Description of round body is given in Column l Velocity of round object and plank when perfect rolling begins is mentioned in Column II Match the entries in Column l with entries in column II Mvu R h gggy MMGR JEG ch fac aag 92 2d 55 M 3 ch ych gest a za 21 Macr azgat effe vo an u a fu uld am uz ho a44 th dis aed 42 YG M grey Gr 21 dagk azg a QCI G H L 4 T I J CH A HIRIN 7 air naich a d am ac ch n fa 1 1 ufafu Ama s 11 A a Column l Solid sphere Hollow sphere CATA Ring C CRY Vo Disc d ucha a p t Column II 7 9 N Vo vo VO P qr S

4 Two rays of light are incident normally on water Bo the rays pass through glass slabs of different height as shown in the figure Refractive indices of water an glass are 4 3 and 3 2 respectively If c is the speed light in vacuum then the time difference between th rays of light to reach the bottom is A C H 2c H hy h 3c B D H 8H 9c h h 6c

Two circuits are shown in the figure a b At a frequency of rad s the average power dissipate in one cycle will be same in both the circuits 50 R 220 V 40 F C 50 R 220 V 0 1 H mooooo L

The figure shows two large closely placed parallel nonconducting sheets with identical positive uniform surface charge densities and a sphere with a uniform positive volume charge density Four points marked as 1 2 3 and 4 are shown in the space in between If E E E3 and E are magnitude of net electric fields at these points respectively then d 1 2 d 3 4 sphere d d 1 E E E E4 2 E E E E

20 180 Two similar circular coaxial loops carry equal currents in the same direction If the loops are brought nearer what will happen Current will increase in each loop Current will decrease in each loop Current will remain same in each loop Current will increase in one and

A series LCR circuit is connected to an AC source of variable frequency When the frequency is increased continuously starl from very small value the power factor a kada ng AC for a fa e HA URA GI R FRAR LCR a di da vida quis A Goes on increasing continuously PROIR CECI ERI SIL B Goes on decreasing continuously Apar ucala JUTI C Remains constant faud 21 D Becomes maximum at a particular frequency food Prica angla BUH BI GIAL

An open glass tube is immersed in mercury in such a way that a length of 8 cm extends above the mercury level The open end of the tube is then closed and sealed and the tube is raised vertically up by additional 46 cm What will be length of the air column above mercury in the tube now Atmospheric pressure 76 cm of Hg 1 38 cm 3 16 cm 2 6 cm 4 22 cm

1 4 particle is moving along a straight line The distance traveled from the starting position of th e particle 3 seconds later is 180 cm and the distance traveled in the next 5 seconds is 220 cm W hat will be the velocity of the particle after 9 seconds

Light rays from a very small object im water falls on the bubble of radius R Assume tha the object is very close to the surface of the 4 bubble Refractive index of water is 3 Take the approximation sine 0 and cose 1 where 0 is angle and consider the rays close to a diameter of the bubble Use the following formula to solve the problem sina sin sin y a b C XELL C Object a a see figure R b The image is from the center of the bubble Y Jame Air bubble Water 1 Virtual and formed at a distance 3R 2 2 Virtual and formed at a distance 3 Virtual and formed at a distance 2R 3 3R 5

Yourself Two charges 10 C and 10 C are placed 5 mm apart Determine the electric field at a A point P on the axis of the dipole 15 cm away from its centre O on the side of the positive charge b A point Q 15 cm away from O on a line passing through O and normal to the axis c the dipole

It is observed that only 0 39 of the original radioactive sample remains undecayed after eight hours Which one of the following is incorrect a the half life of that substance is 1 hour 1 b the mean life of the substance is In 2 hour

An isolated metallic spherical thin shell has given a charge Q as shown The parameter r is the distance to be measured from center of sphere Which of the following statement s is are CORRECT Q R A The energy stored in space R r 2R is B The energy stored in space R r 2R is C Energy stored in space 0 r R 2 is Q 16 OR 32 ER Q 16 OR D If switch S is closed the heat generated in wire is S Q STEOR

Block 1 sits on top of block 2 Both of them have a mass of 1 kg The coefficients of friction between blocks 1 and 2 are 0 75 and 0 60 The table is frictionless A force P 2 is applied on block 1 to the left and force P on block 2 to the right Obtain the minimum value such that both blocks move relative to each other and fill P 2 in OMR of P P min min P 2 1 2

3 Match List I with List II and select the correct answer using the codes given below the lists List I List II P Photodiode 1 Light into electrical energy Q Zener diode 2 Electrical energy into light R Solar cell 3 Optical signal S LED 4 Voltage regulator Codes P a 2 b 4 c 1 Q R 3 4 1 2 2 3 S 1 3 34 4

NS Two blocks each having a mass M rest on frictionless surface as shown in the figure If the pulleys are light and frictionless and M on the incline is allowed to move down then the tension in the string will be A 2 3 Mg sin 0 Mg S sin 0 B Mg sin 0 x1 2 D 2 Mg sin 0 66 lirts 126

One mole of diatomic ideal gas undergoes a cyclic process ABC as shown in figure The process BC is adiabatic The temperatures at A B and C are 400 K 800 K and 600 K respectively Choose the correct statement 1 The change in internal energy in the process AB is 350 R 2 The change in internal energy in the process BC is 500 R 3 The change in internal energy in whole cyclic process is 250 R The change in internal enorm in the process CA is 700 P P A B 800 K 400 K 600 E C

elar Anstyals through Continuous Exercise The figure shows three identical rods each of mass M and length L then the moment of inertia of the system about axis AB will be 1 A ML 12 2 ML B ML 3 3 4 9 ML2 2 1 M 3 If C

4 a A few identical cells are first joined in series and then in parallel Under what condition will both the combination send the same current though the external resistance R b In a closed coil there are n number of cells connected in series E M F of each cell is e internal resistance r and the connecting wires are resistanceless What reading will the voltmeter give when connected across any one of the cells Assume that the voltmeter has infinite resistance

A charge q 10 C of mass 2 g fig is free to move when released at a distance a from the fixed charge Q Calculate its speed when it recedes to a distance b Assume a 1 m b 10 m Q 103 C Qaq fixed 90 m s b 2 9 m s 3 900 m s 4 none of these BUE 45

A circuit contains uncharged capacitor resistor and a battery as shown The switch is closed at t 0 and the system is allowed to attain steady state Now the switch is opened Pick the CORRECT statement s f R www S A Heat generated in resistance till steady state is CV B If after a long time switch is opened and a dielectric is inserted between the complete volume within the capacitor then the new energy stored in capacitor is kCV 2 C If after a long time switch is opened and a dielectric is inserted between the complete volume within the capacitor then the new energy stored in capacitor is D Ratio of electric field just after and before dielectric is inserted is 1 CV 2k

SolveLancer Test A dipole is kept at centre of a spherical metal shell as shown in the diagram What is the force on charg Q placed at a distance of r from the centre of shell a Data insufficient b kqQa 23 c Zero SolveLancer Test

Q6 A stone of mass is 1 kg tied 1 point to the end of a string of length 1 m whirled in horizontal circle with a uniform angular velocity of 2 rad s 1 The tension of the a 2N b string is 1 3N c 4 N d 1 4N O A B O C O D O Other

A trianguler pulse moving at 2cm s on a rope approches an end at which it is free to slide on vertical pole What is the particle speed at the free end at sec from the instant shown 3 4 1cm 1 2cm s 3 3cm s 1cm 2cm s 1cm 1cm 2 1cm s 4 4cm s

A particle of mass m penetrates a medium at a speed to where it experiences a resistance proportional to the square of its speed with constant of proportionality k 0 Gravity may be ignored a What is the speed of the bullet as a function of position within the medium Use the initial condition v to at x 0 b Using the initial conditions v vo and x 0 at t 0 show that kvot 1 1

Q8 Four point masses 1 kg 2 kg 3kg and 4 kg are located at the corner A B C and D respectively of a square ABCD of side 1m Then the radius of gyration of the system about AB as axis of rotation is a 0 3866 m b 0 8366 m c 0 6683 m d 0 6638m A B O C O D Other 1 poin

In the circuit shown here the point C is kept connected to point A till the current flowing through the circuit becomes constant Afterward suddenly point C is disconnected from point A and connected to point B at time t 0 Ratio of the voltage across resistance and the inductor at t L R will be equal to 2 1 c 4 1 1 1 3 c A B R www

20 The plates of a parallel plate capacitor are 4 cm apart the first plate is at 300 V and the second plate at 100 V The voltage at 3 cm from the second plate is b 400 V a 200 V c 250 V d 500 V 1 The potential of a charged spherical conductor of radius ris 10 Y The 1