Physics Questions

A cylindrical capacitor has length 54 cm and radii 4 cm and 3 cm Potential of the inner cylinder when it is given a charge InC and outer cylinder is grounded 1 10 volt 3 105 volt 2 10 volt 4 10 volt

at A and B are same An air capacitor has capacitance 70 F with a separation between plates 20 mm Now distance between plates is doubled and dielectric of k 2 thickness 10 mm is inserted between the plates of capacitor then its capacitance becomes 1 35 F 2 40 F 3 50 F

Two charge 6 C and 4 C are separated at distance 15 cm apart then the point on the line joining the charges where electric potential is zero is 1 At distance 6 cm from 6 C 2 At distance 45 cm from 6 C 3 At distance 30 cm from 6 C 4 At distance 60 cm from 6 C 30

O Single Correct MCQ The pressure that has to be applied to the ends of a steel wire of length 10 cm to keep its length constant when its temperature is raised by 100 C is For steel Young s modulus is 2x 10 N m 2 and coefficient of thermal expansion is 1 1 x 10 5 C A B C 2 2 107 Pa 2 2 106 Pa 2 2 108 Pa

A When the magnetic flux through the loop decreases w r t position then there is induced emf in the loop R The direction of induced current is in such a way that it decreases the magnetic flux incide

Adjacent graph is drawn for particle along straight line motion a Acceleration v velocity Find displacement of particle in meters from re till it acquires velocity 2 ms 1 3 4 v m s2

46 A body of mass m 4 kg is acted upon by a constant 46 m 4lgt 1 force such that its position varies with time as r 1 5 The work done by the force in time interval t 1 second to t 3 second e 64 J 2 3 47 Two soap bubbles of radius 38 38 71 K T2 S bok 4 4X4 1642 1 515 and come in contact hach other Radius of curvature of the common 22100 he Si 477

37 A metal sphere of radius R is given a potential 37 V then energy stored inside the concentric sphere of radius 2R is 1 TE RV 3 2 RV 2 17 TE RV 4 4 RV

Phy Section A This section contains 20 SINGLE CORRECT TYPE questions Each question has 4 choices 1 2 3 and 4 out on The unit of self inductance is Volt meter Volt ampere Volt second volt second ampere

Resistance of AB wire is 2000 2 and resistance of voltmeter is 1500 2 If sliding contact is in the middle of AB wire then reading of voltmeter will be V 16volt 1 3 V 3 10 V 75007 B www A 2 6 V 4 8V 750 t 8 V

Board Competitive Exams 41 Two projectiles of same mass and with same velocity are thrown at an angle 60 and 30 with the horizontal then which will remain same 1 Time of flight 2 Range of projectile 3 Maximum height acquired 4 All of these 42 Two particles having mass M and m are moving in a circular path having radius R and r If their time periods are same then the ratio of their angular velocities will be 3 1 43 If A B A 181 and B will be 1 90 3 0 R 4 then angle between A 2 120 4 60 44 A particle moves along a circle of radius with constant tangential acceleration If the velocity of the particle is 80 m s at the end of the second revolution after motion has begun the tangential acceleration is 1 40 m s 2 640 m s 4 40 m s 3 160 m s 45 The vector sum of two forces is perpendicular to their vector differences In that case the forces 1 Are equal to each other 2 Are equal to each other in magnitude 3 Are not equal to each other in magnitude 4 Cannot be predicted 46 A wheel has angular acceleration of 3 0 rad s and an initial angular speed of 2 00 rad s In a time of 2 s it has rotated through an angle in radian of 1 10 2 12 3 4 m 47 A particle is moving such that its position coordinates x y are 2 m 3 m at time t 0 6 m 7 m at time t 2 s and 13 m 14 m at time t 5 s 1 2 SECTION D Assertion Reason Type Questions In the following questions a statement of assertion A is followed by a statement of reason R 3 Motion in a Plane 225 Average velocity vector V from t 0 to f 5 s is 1 13 147 3 2 1 1 5 1 If both Assertion Reason are true and the reason is the correct explanation of the assertion then mark 1 2 If both Assertion Reason are true but the reason is not the correct explanation of the assertion then mark 2 3 If Assertion is true statement but Reason is false then mark 3 4 If both Assertion and Reason are false statements then mark 4 A If ALB then A BI IA BI R If ALB then A B is perpendicular to A B A The addition of two vectors P and Q is commutative R By triangle law of vector addition we can prove P Q Q P A A vector cannot be divided by other vector R A vector can be divided by a scalar 4 A At the highest point the velocity of projectile is zero R At maximum height projectile comes to rest A Horizontal range of a projectile is always same for angle of projection with horizontal or 0 with vertical R Horizontal range depends only on angle of projection

Two identical narrow slits S and S2 A very small completely absorbing strip is placed at distance y from the point C C is the point on the screen equidistant from S and S2 Assume d D where d and D have usual meanings When S2 is covered with a thin film of thickness t and refractive index of then shift in central to maximum is P A td 1 D tD 1 towards S2 towards S2 B td D towards S tD 1 towards S

5 If a solid is floating on a liquid then which of the thermal following statements is wrong a coefficient of linear expansion of solid y thermal coefficient of cubical expansion of liquid 1 If y 3a then upon heating the solid will float with more fraction of volume in the liquid 2 If y 3x then upon heating the solid will float with lesser volume in the liquid 3 If y 3a then upon heating the fraction of volume of solid in liquid remains constant Both 2 3

correct If time taken by a pendulum to complete 20 vibrations is 60 60 s then time period of the pendulum in s up to appropriate significant figures is 03 03 s 3 0 s htains 20 SINGLE CORRECT TYPE questions Each question has 4 choices 1 2 3 and 4 out of which only one is O3 00 s 21 26 31

Resistance of a wire at any given temperature C is given by R 0 R 1 ad ao where apare positive constants and R is the temperature at 0 C The temperature coefficient of the material of wire is a Be a pe a Be a Bel 02 B 6

105 100 g ice at 0 C is dropped into a calorimeter of water equivalent 100 g containing 100 g water at 40 C Resulting temperature of the mixture at equilibrium is 1 0 C 2 20 C 3 5 C 4 10 C

A particle is projected with an unknown velocity at and angle of 45 with an unknown velocity at an angle of 45 with horizontal It grazes the top of a pole at a distance of 4m from the point of projection and falls 6m behind the pole If the height of pole is 4n 10 in metre then the value of n is

Statement l For a binary solution of two known liquids A and B with the knowledge of density of solution molarity can be converted into molality Statement II Molarity changes with change in temperature O Statement I is correct but II is incorrect Statement II is correct but I is incorrect Both the statements are correct Both the statements are incorrect

DE02 BOAHBO NCERT BASED OBJECTIVE PHYNELECTROSTATIC POTENTIAL CAPACITANCEP65 29 Curve A and B represents variation in el field and potential of a point charge ther E or V A B 1 A represents electric field 2 B represents electric field 3 Any of the curve may represent ele and potential 4 Can t be determined

In the given figure charge on capacitor C C 2 F H C 1 F 1 22 C C 4 F HH HH 66V C 3 F 2 44 C

The value of acceleration and friction force in the given diagram is Ms 0 4 MK 0 3 53 F 500N 12 kg 1 4 m s upward 120 N 2 4 m s downward 120 N 3 5 m s upward 36 N 4 5 m s upward 120 N

A In the case of ground to ground projection of a projectile from ground the angle of projection with horizontal is 0 30 There is no point on its path such that instantaneous velocity is normal to the initial velocity R Maximum deviation of the projectile is 20 60

charge then B 1 Sign of V V is negative B 2 Sign of work done by external agency in moving a negative charge from B to A is negative 3 Sign of work done by the field in moving a positive charge from A to B is positive 4 Sign of work done by the external agency in of 237 moving a negative charge from B to A is positive 1

long cylindrical conductor of cross sectional area S is made of a material whose resistivity depends only the distance r from the axis of the onductor as p where is a constant The resistance per unit length of such a conductor is N The value of N is S

com Two cylindrical conductors with equal Cross section and different conductivity and o are connected in series end to end If current I flows through his combination then O Current density J is different for both conductors O Electric field strength E is same in both conductors At junction of these conductors there will be no charge accumulation At junction of these conductors there will be some charge accumulation Th

34 An ideal gas is made to expand from an initial volume V to a final volume 4V through three different thermodynamic processes as shown in figure Process 1 is adiabatic 2 isothermal and 3 isobaric If AU AU and AU denote the change in internal energy of the gas in the three processes respectively then P4 1 AU AU AU3 AU 3 AU AU AU3 TI HT T V MCV wat X TV T C 4V 2 AU AU AU 4 AU3 AU AU

5 Work done against electrostatic force in bringing a unit positive charge from infinity to a point is 1 Equal to the electrostatic potential V at that point 2 equal to the negative of work done by electrostatic forces 3 Both 1 2 4 Neither 1 nor 2 16 Uchi Felf 1 2

3 If dielectric constant and dielectric strength be denoted by k x respectively then a material suitable for use as a dielectric in a capacitor must have 1 high k high x 3 low k high x 2 high k low x 4 low k low x

25 A small sphere of radius r having charge q is 25 r enclosed by a spherical shell of radius r having charge q Which charge will necessarily flow from the sphere to the shell when connected 1 9 2 9 4 May be q 3 both 1 and 2

A 50 KW DC generator produces a potential difference 250 V If the resistance of the transmission line is 12 what percentage of the original power is lost during the transmission Answer

3 A sinusoidal ac current passes through a resitor o resistance R in LCR series circuit If phase difference between supplied voltange and supplied current is and peak value of supplied current is I then power dissipated in the ckt is 1 IR cose 3 IR 2 4 IR 2 IR cos 0

a 15 m b 25 m c 35 m Q 95 A stone is dropped from a height h Simultaneously another stone is thrown up from the ground which reaches a height 4 h The two stones cross each other after time a h 8g b 8hg c 2gh d h 2g

5 A block is kept on a fixed inclined plane of inclination 60 as shown Coeficient of friction 1 between the block and the incline is To keep the block at rest minimum external force should be applied along the vector 1 31 1 3 3 1 1 60 X 2 i 3 4 31 1

lons Each question has 4 choices 1 2 3 and 4 out of which only one is correct For the given potentiometer set up A is a primary cell which drives the setup J is null point for no deflection in the galvanometer Then choose the correct statement Rh Hwiw O R If R increases J will moved to the right For measuring r E should be always less than that of V If Rh increases J will shift towards right All are correct

A At the highest point the velocity of projectile is zero R At maximum height projectile comes to rest

67 An iron tyre is to be fitted onto a wooden wheel 1 metre in diameter The diameter of the tyre is 6 mm smaller than that of the wheel The tyre should be heated so that its temperature increases by a minimum of coefficient of volume expansion of iron is 3 6 10 5 C X 1 167 C 3 500 C 2 334 C 4 1000 C

R Maximum deviation of the projectile is 20 60 A Three vectors having magnitudes 10 10 and 25 cannot produce zero resultant R If three vectors are producing zero resultant then sum of magnitude of any two is more than or equal to magnitude of third and difference is less than or equal to the magnitude of third

gm of ice at 20 C is kept into a calorimeter containing 10 gm of water at 10 C The specific heat of water is twice that of ice When equilibrium is reached the calorimeter will contain 2 20 gm of ice 1 20 gm of water 4 5 gm ice and 15 gm water 3 10 gm ice and 10 gm of water 17 Water falls from a height 500 m What is the rise in temperature of water at bottom if in the water 1 0 06 0 3 3

A molecule of a substance has dipole mome 10 c m One mole of this substance polarised by applying a strong electric fie 10 V m If direction of electric field is sudder changed by an angle 60 then heat released the substance for the new allignment of dipoles 2 06 J 3 3 J 4 6 J

Two plane mirror arc enclined to each other as show ray of light is incident at an angle of 30 on one of the The ray after reflection falls on second mirror and fina retrace its path calculate the angle between mirror 1 60 2 20 CE 30 2 45 4 4 0 G

4 A human body has a surface area of approximately 1 m The normal body temperature is 10 K above the surrounding room temperature To Take the room temperature to be To 300 K For To 300 K the value of o 460 Wm 2 where o is the Stefan Boltzmann constant Which of the following options is are correct A The amount of energy radiated by the body in 1 second is close to 60 Joules B If the surrounding temperature reduces by a small amount AT To then to maintain the same body temperature the same living human being needs to radiate AW 40T3ATO more energy per unit time C Reducing the exposed surface area of the body e g by curling up allows humans to maintain the same body temperature while reducing the energy lost by radiation D If the body temperature rises significantly then the peak in the spectrum of electromagnetic radiation emitted by the body would shift to longer wavelengths

D A Uniform circular motion is accelerated motion still speed remains unchanged R Instantaneous velocity is always normal to instantaneous acceleration in uniform circular motion

A particle is released from rest from a top of incline plane of angle 37 Top rd is smooth and bottom 3rd is rough If again come to rest at bottom Friction co efficient is a 3 8 b 3 16 c 3 4 d 9 8

10 A particle starts from rest at x 0 and acceleration varies with x as shown in the figure Then a m s 4 x m 1 The particle comes to rest at x 20 m 2 Maximum velocity in positive x direction is 4 5 m s 3 Velocity at x 10 m is 60 m s 4 Distance covered by particle till it returns to initial position is 80 m

ion A Section contains 20 SINGLE CORRECT TYPE questions Each question has 4 choices 1 2 3 and 4 out of which only one is correct a 6 respectively then the maximum percentage error in Pis c d A physical quantity Pis described as P 07 05 03 If maximum percentage error in measurement of a b c and dare 2 1 and 3

Are not equal to each other in magnitude 4 Cannot be predicted 6 A wheel has angular acceleration of 3 0 rad s and an initial angular speed of 2 00 rad s In a time of 2 s it has rotated through an angle in radian of 1 10 2 12 3 4

tan a Velocity v versus time 1 graph of a particle moving in a straight line is shown in the figure If tan B particle till the time its velocity becomes zero is v m s 1 s 2 then average speed of the E 36

In the figure the potentiometer wire AB of length L has resistance 5r is joined to the cell D of emt E and internal resistance The cell C semfis resistance is 2r The galvanometer shows zero deflection when AJ 5 Then the value of a is P w lesi and its internal

For the circuit shown the power dissipated in the external variable resistance R is plotted against R The value of internal resistance of cell e is O r 360 O r 130 O r 4 O r 60 90

one hereas B IS a equal base area and height are arranged as shown in figure A is a hollow uniform thin conical shell without base If centre mass of the system of two cones lies on the common base find the ratio of their masses MA MB O O A 3 4 4 3 H H MA MB