Basic Physics Questions and Answers

2 6 For the arrangement shown in figure the tension in the string to prevent it from sliding down is m 1 kg 1 6 N 19 O ANT 37 0 8 2 6 4 N AT

A block of mass m is kept over a rough board such that it is connected to a spring whose other end is also fixed to the board The board is lifted slowly to increase the inclination with horizontal The graph that best represents the variation of elongation in spring with 0 is X 3 XA XA 0 Horizontal 0 mt00000000 0 XA 2 0 V 1 XA 4 A

tion 5 The reason that freshly laundered laundry does not touch the ground is that proportional to the weight of the laundry but in the opposite direction O O The string exert action The floss exert the action The string exotic reaction The cloth exert reaction

A signal of 5 kHz frequency is amplitude modulated on a carrier wave of frequency 2 MHz The frequencies of the resultant signal is are a 2005 kHz 2000 kHz and 1995 kHz b 2000 kHz and 1995 kHz c 2 MHz only d 2005 kHz and 1995 kHz

Bu B Br An infinitely long wire is bent at 90 at point O 25 as shown in figure Match the following Table I Table II A Magnetic field at P P inwards B Magnetic field at Q Q outwards 1 A P B Q S 3 A R B Q S I R TEXT SERIES R S 10 1 4x r 2 A P S B Q S 4 None of these van ser end and O 3 BB B B 4 B B B B v far segen 90 farg fear ffera B A P B Table I 1 A P B Q S 3 A R B Q S 45 P R S Table II 2n r 47 T 2 A PS B Q S 4 340

Q 12 In a certain double slit experimental arrangement interference fringes of width 1 0 mm each are observed when light of wavelength 5000 is used Keeping the set up unaltered if the source is replaced by another of wavelength 6000 the fringe width will be 1 0 5 mm 3 1 2 mm 2 1 00 mm 4 1 5 mm

A man is running with a constant acceleration on a plate which is placed on a horizontal smoot surface Then choose the correct option s A Work done by friction on the man is negative P Work done by friction on the man is positive C Work done by friction on the plank is positive D work done by friction on the plank is negative

1 A wooden wedge of mass M and inclination angle a rest on a smooth floor A block of mass m is kept on wedge A force F is applied on the wedge as shown in the figure such that block d remains stationary with magnitude of force F is a M m g tan a c mg cos a F4 M respect to wedge So b g tan a d M m g cosec a

An elastic ring of mass m and force constant k stiffness is released from rest in a smooth cone of semi vertex angle 0 from horizontal position as shown in figure Initially the ring was in natural length A initial acceleration of any point on circumference of ring is g B initial acceleration of centre of ring is g cos 0 mg cot 0 2 k D at the moment maximum vertical displacement acceleration of centre of ring is zero C maximum vertical displacement of centre of ring is ring g

Ans given is 3rd but when I solved it by Nernst equation my ans is 0 29V Calculate EMF of the cell A A3 0 1M B2 0 01 M B Given E 0 75 V 1 R A A3 0 45 V E B B 1 2 3 4 0 30 V 1 21 V 0 26 V 0 80 V

0 A truck is stationary and has a bob suspended by a light string in a frame attached to the truck The truck suddenly moves to the right with an acceleration of a The pendulum will tilt NEET 2019 Odisha 1 to the left and angle of inclination of the pendulum with the vertical is sin g 2 to the left and angle of inclination of the pendulum with the vertical is tan a g 3 to the left and angle of inclination of the pendulum with the vertical is sin a g 4 to the left and angle of inclination of the a

In the given A C circuit the instantaneous current through inductor and capacitor are 0 8 A and 0 4 A respectively The instantaneous current through the resistor is 1 1 2 A 2 0 6 a wwwww R 3 0 4 A 4 V0 8 A 000000 Htc

Two thin lens have a combined power of 10 D in contact When separated by 20 cm their equivalent power is 6 25 D Find their individual powers in dioptres A B C D 3 5 and 6 5 5 and 5 7 5 and 2 5 9 and 1 Correct Answer

O APPARENT WEIGHT Because of upward force acting on a body immersed in a fluid either wholly or partially there occurs an apparent loss in weight of the body The net weight of an object immersed in a fluid is called apparent weight W W Th W is the true weight of the body App Decrease in weight W WA App Note i Using Archimedes s principle we can determine relative density R D of a body as R D Th Weight of the fluid displaced density of body wt of body density of pure water at 4 C wt of equal volume of water wt of body thrust due to water wt of body loss of wt in water wt of body in air wt in air wt in water ii If a body is weighed in air WA in water W and in a liquid W loss of weight in oil WA W loss of weight in water W W then specific gravity of oil

2 A mountain climber is sliding down a vertical rope Her total mass including equipment is 65 kg By adjusting frictional force of the rope she controls the force that the rope exerts on her For a 2 0 s interval this force T is shown as a function of time t in the given graph What is change in her speed in this interval Assume acceleration of free fall to be 10 m s and neglect air resistance a 5 m s c 15 m s b 10 m s d 20 m s 3 A boy of mass 50 kg is standing at one end of a 90 m long boat of mass 650 325 ATIN 0 2 tls 2 0

A prism of a certain angle deviates the red and blue rays by 8 and 12 respectively Another prism of the same angle deviates the red and blue rays by 10 and 14 respectively The prisms are small angled and made of different materials The dispersive powers of the materials of the prisms are in the ratio A B 5 6 9 11

small distance d as shown The fringes obtained on the screen will be tous S S d B A points C D straight lines semi circles Screen

A transverse wave is represented by the 2 equation y yo sin value of is the maximum particle velocity equal to two times the wave velocity Your Answer 2 A B C 3 vt x For what 2 Correct Answer

A diverging lens of focal length 10 cm is placed 10 cm in front of a plane mirror as shown in the figure Light from a very far away source falls on the lens The final image is at a distance A B C D 20 cm behind the mirror 7 5 cm in front of the mirror 7 5 cm behind the mirror 2 5 cm in front of the mirror Correct Answer

12 A block of mass m is moving with a constant 12 acceleration a on a rough horizontal plane If the coefficient of friction between block and the ground is u then the power delivered by external agent at time t is 1 mat 3 um a ug gt 2 umg at 4 m a ug at yra fa fa in gutes at et af H eft 1 mat 3 m a ug gt 2 umg at 4 m a g at

Since direction of induced current is given in dia Therefor e magentic field produced according to the induced curre nt is vertically downward right hand thumb rule So the direction of magentic field should be vertically upward 19 For given arrangement in horizontal plane the possible direction of magnetic field 1 towards right 2 towards left 3 vertically upward 4 vertically downward Induced current mim because in motion 16 Eweley has

9 An air column in a tube 32 cm long closed at one end is in resonance with a tuning fork The air column in another tube open at both ends of length 66 cm is in resonance with another tuning fork When these two tuning forks are sounded together they produce 8 beats per second Then the frequencies of the two tuning forks are Consider fundamental frequencies only E 2013 1 250 Hz 258 Hz 3 264 Hz 256 Hz 2 240 Hz 248 Hz 4 280 Hz 272 Hz

3 27 ms 4 36 ms 1 32 A ball is dropped from the top of a building The ball takes 0 5 sec to fall past the 3 m height of a window some distance from the top of the building If the speed of the ball at the top and the bottom of the windou are v and v respectively then g 9 8 m s 2 V VB 4 9 m s 1 V VB 12 m s 3 V V 1 m s 4 VT 1 m s

39 In the given diagram two particle A B having same charge mass respectively m m are moving in a magnetic field B with speed vand V then 1 MAY Me Va 2 MAVA My VB 3 m me and VA VB 4 m mg and VA VB He ALLEN 29 and fax 27 vero cha B VYB 1 MA VA M a 2 m vmeye 3 mm 12 AVB 4 m m 1 V VB

32 4 1 g 2 g 2 3 g 3 4 g 4 If acceleration of the system is 2 m sec then 32 value of T is T T Ikg lkg 1kg 3 3 N 1 IN 2 2 N The 4 4 N 1 g 3 g 3 4 g 4 af farv 2m sec T B BM 1kg 2 g 2 H T 1 IN 2 2N Ikg 3 3 N 1kg 4 4 N

When a piece of non metal and a metal are dropped from the same height near the surface of the earth the non metallic piece will reach the ground first Induced current in metal will decrease the acceleration 7 electric fi R Direction variable aw A If the varies will

A compound microscope has a magnification of 30 when final image is formed at 25 cm from the eye piece What is magnification produced by the objective if the focal length of eyepiece is 5 cm 5 0 O 7 2 10 0 2 5

A material has normal density p and bulk modulus K The increase in the density of the material when it is subjected to an external pressure P from all sides is Question Type Single Correct Type 1 P PK 2 K PP 3 pP K ok D

16 Tension in the lower string is 20 N If natural length of spring is 10 cm then the length of the spring which is connected between 2 kg and 4 kg block as shown in figure is 201 1 9 cm Sol Answer 3 2 10 cm m 2 kg K 60 N cm m 4 kg T 20 N 3 11 cm 4 12 cm

The angle between two vectors given by 61 63 3k and 7i j 4k is B D C COS 4 cal Correct option is D sin We know angle between two vectors is given by A B cos 8 A A B A 62 62 3 9 B 72 4 4 9 And A B 61 61 3k 7i 4j 4k 42 24 12 54 Now putting the above values in A we get 8 cos 0 sin 0 sin Tage 54 81 1 3 When we are multiplying 6i 6j 7i 4j 4k We do like this 6x7 6x4 j 3x4 k 42 24 12 because i 2 j k And not like the way we generally d multiplication in maths when we ar variables like this 61 71 4 4k 6 71 4 4k 3k 7i 4j 4k Can you please explain why it is so

Han 8 1 37 A detector is released from rest over a source of sound of frequency fo 10 Hz The frequency observed by the detector at time t is plotted in the graph The speed of sound in air is g 10 m s ONS a 330 m s c 300 m s f Hz 2000 1000 30 t s b 350 m s d 310 m s

HIS and secondary of a 20 mH and 90 mH al induction between and resistance for ter NEET Part II A train is moving on a straight horizontal track Induced emf across the axle is maximum when it moves 1 At poles 2 At equator 3 Along the direction where angle of dip is 45 4 emf is not induced A square loop enters a magnetic field with velocity v as shown in figure The front edge enters the magnetic field at time t 0 Which of the following anh gives the correct variation of emf induced 3 PA 4 d 10 53 Self inductance of a s decreasing through it induced in the solen

An electric bulb is marked 100W 220V If the supply voltage drops to 110V what is the total energy produced by the bulb in 20 minutes 1 Point O 30kJ O 15kJ O 10kJ O 5kJ

A parallel plate capacitor is charged to 60 C 7 Due to a radioactive source the plate loses charge at the rate of 1 8 x 10 C s the magnitude of displacement current is 1 1 8 10 C s 2 3 6 10 C s 3 4 1 10 C s 4 5 7 x 10 2 C s x 60 fera ti ya 1 810 C sta effet 1 1 8 x 10 2 3 6 10 3 4 1 x 10 C s 4 5 7 x 10 2 C s C s C s

A mass M is divided in two parts m and M m 35 Now two parts are connected by an ideal string passing over a pulley as shown in diagram Find value of m such that tension in string is maximum 1 m 0 3 m M m M m 2 m 4 m M M 34 di via facer y farcit Bicht Jordi gesucri reit s s i m s fra safe 1 m 0 MM m 3 m M 3 M m 2 m 4 m MN MA

10 In a resonance tube experiment resonance occurs with a tuning fork of 1 point frequency 420 Hz when the resonating length of the air column is 20 cm What is the velocity of sound in air Oa 300 m s Ob 336 m s Oc 310 m s Od 320 m s

A body performs linear S H M with amplitude a When it is at a distance from 3 extreme position the magnitude of velocity is times the magnitude of acceleration The period of S H M is 3 2 5 A B C D 5T 3 5 2 T 3 5 TT S S S S

28 A ball is dropped from height h and after striking with the ground it rises up to height h The coefficient of restitution between the ball and the ground is 1 3 h ho h Whe 2 4 h ho 2 ho

3 ALLEN Three blocks A B and C of masses 8 kg 4 kg 23 and 2 kg respectively are in contact on a frictionless surface as shown If a force of 28 N is applied on the 8 kg block then the contact force between A and B is A B 1 12 N 3 36 N C 2 16 N 4 4 N 8 kg 4 kg 2 kg 30 A B Caran 8 kg dupla uas uz uzuk B1 afe 28 N Trifa faxan Gua B 1 12 N 3 36 N A B C 2 16 N 4 4 N

40 At t 0 observer and source are at same place Now the source is projected with velocity 60 2 m s at 45 Natural frequency of source is 1000 Hz Find the frequency heard by the observer at t 2 s Take speed of sound 340 m s a 930 Hz c 826 Hz b 860 Hz d 970 Hz

27 3 1 27 x 10 N 4 0 127 N A body A of mass m exerts a force on another 27 body B of mass m If the acceleration of B be a2 then the acceleration in magnitude of A is m2 mi 82 mi 3 82 m 2 m m a 4 m m a LEADER TEST SERIES JOINT PACKAGE COURSE HEET UG 2021 02082020 3 1 27 10 N 4 0 127 N A m o a arifi anti a 3 m mi m a2 82 Space for Rough Work ferg Gu B Ba a A 2 mm a 4 m m a 0999DMD310320003 LIS Page 9 48

22 The equation for the vibration of a string fixed at both ends vibrating in its third harmonic is given by y 2 cm sin 0 6 cm cos 500 ps t The length of the string is a 24 6 cm c 20 6 cm b 12 5 cm d 15 7cm

4 capacitors each of 2 F are connected as shown What will be the equivalent capacitance across the points A and B 1 Point A C1 C3 B C2 C4

A convex surface of radius of curvature 40 cm separates two medium of refractive indices and 4 3 1 50 An object is kept in the first medium at distance of 20 cm from the convex surface What is image position O 24 cm from pole 30 cm from pole O 18 cm from pole 36 cm from pole

A coil has 500 turns and the flux through the coll is 32 4t 9 milliweber The magnitude of induced emf between the ends of coil at t 5 s is 1 34 milivolt 2 17 volt 3 17 milivolt 4 34 volt

15 What is a rectifier used for a Convert ac voltage to dc voltage Ob Convert dc voltage to ac voltage Oc Measure resistance O d Measure current

The angular diameter of a planet measured from earth is 90 If the diameter of the planet is x 10 m then its distance from the earth is B 7 2x10 m E 1 8 108 m A 3 6 10 m D 7 2 106 m C 3 6x 106 m

2 Minimum frequency of audible sound is 20 Hz and maximum frequency is 20 000 Hz If we compare the sound levels of these two frequencies of same amplitudes their difference will be a 30 dB b 60 dB c 90 dB d 120 dB

When light is refracted into a medium from vacuum then Its wavelength and frequency both change Its wavelength increases but frequency remains same Its wavelength decreases but frequency remains same Its wavelength and frequency both decrease

3 dielectric strength 4 dielectric constant Two large metal plates are placed parallel to 3 each other The inner surface of plates are charged by and coulomb m The electric field between the plates and outside the plates to e 3 Eo Eo o 2 0 zero 4 zero zero 3 ang fer for 3 20 4 qurdgal atingere con s t m zero 6 4 I 20 Eo zero zero