Basic Physics Questions and Answers

When white light passes through glass prism one gets spectrum on other side of the prism In the emergent beam the colour which is deviating least is O Violet ray O Red ray O Green ray

4 unchanged A block of mass m rests on a platform The platform is given up and down SHM with an amplitude d What can be the maximum frequency so that the block never leaves the platform 1 g d 3 g d 2x 2 2x g d 4 2n d g

There are two statement statement 2 points 1 When a ferromagnetic sample is subject to a cycle of magnetization then magnetizing field H lags behind the corresponding intensity of magnetization M statement 2 Materials having small coercive forces are called soft magnetic material Which option is more correct O Statement 1 Statement 2 are incorrect O Statement 1 is correct Statement 2 is incorrect O Statement 1 Statement 2 are correct Statement 1 is incorrect Statement 2 is correct

a 4 There are two coils A and B as shown in the figure A current starts flowing in B as shown when A is moved towards g 0 B and stops when A stops moving The current in A is counterclockwise B is kept stationary when A moves We can infer that a there is a constant current in the clockwise direction of A b there is a varying current in A c there is no current in A d there is a constant

est 6 CC 26 A capacitor of capacitance C 1 F withstand a maximum voltage V 6 kV while a capacitor of capacitance C 3 0 uF withstand the maximum voltage V 4 kV The maximum voltage which the capacitors can withstand when connected in series 1 8 kV 3 10 kV 2 9 kV 4 5 kV

a 24 13 b 40 13 2 A man walks on a straight road from his home to a market 2 5 km away with a speed of 5 kmh Finding the market closed he instantly turns and walks back home with a speed of 7 5 kmh The average speed of the man over the interval of time 0 to 50 min is equal to

1 cot x 1 1 x If y loge 1 tan x dy then find the value of x 1 when y 1 dx 1 Let cos x dx F x with F 0 dx 100 I w then find F x when x T taking 3

Question No 60 What w v percent of glucose solution is isotonic with 1 5 urea solution 1 5 3 0 4 5 6 0 Marks 4 1

physical situation Two heat conducting pistons can slide without friction in a horizonta made of a heat insulating material Distance between the pistons is 80 The space between the pistons is completely filled with water Dens water and ice are 1000 kg m and 900 kg m respectively specific h water and ice are 4200 J kg C and 2100 J kg C respectively latent heat of fusion of ice is 330 kJ kg and thermal conductivity four times of that of water Heat capacity of the pistons and that of the pip negligible are 26 The left and the right pistons are maintained at constant temperature 40 C and 16 C respectively After a sufficiently long time when steady state is reached what will the distance between the pisto become a 80 5 cm c 88 0 cm b 84 2 cm d 97 5 cm 27 Now the devices maintaining temperatures of the pistons are remov and the pistons are covered with heat insulating materials Afte sufficiently long time when a steady state is reached again what the distance between the pistons become a 80 0 cm c 89 2 cm b 88 9 cm d 92 7 cm

c 41 11 V In the question number 3 the net power consumed over a full cycle is a 586 W c 48 4 W The rms value of current in an ac circuit is 25 A b 242 W d 484 W a FSFL 10 Th re

r drop falls at regular intervals from a tap 9 m 12 9 m3 RED RIG above the ground The fourth drop is leaving the tap at the instant the first drop touches the ground How high is that third drop at that instant 4 1 8 m 2 6 m 7 5 m 4 4 98 m 3 2 2 X 1 8 m 2 6 m 3 7 5 m 4 4 98 m ten a fondi 16x 9 x 16 1124 3x 9 TO 27 16 1

Which amongst the following are compounds ii K PtCl3 C H4 iv Ti 0 C6H5 4 organometallic i Al2 CH3 6 iii N CH3 3 i only iii and iv only i ii and iii i and ii only Marks 4 1

The insulation property of air breaks down when the electric field is 3 x 10 Vm The maximum charge that can be given to a sphere of diameter 5 m is approximately 1 2 10 C 3 2 10 C 2 2 x 10 C 4 2 x 10 C 28

20 gm ingot of metal is heated to 95 C and then dropped into a beaker containing 40 gm of water initially at 20 C If the final equilibrium temperature of the mixed system is 35 C find the specific heat of the metal Given specific heat of water is 1 cal gm C

Question No 56 Rate constant depends on Catalyst Pressure Concentration All of the above Marks 4 1

4 The line that draws power supply to your house from street has a 220 2 V average voltage b 220 V average voltage c voltage and current out of phase by 1 2 d voltage and current possibly differing in phase such that lol 18

A circular punch 10mm in dia is used to punch a hole through a steel plate of 10mm thick If the force necessary to drive the punch through the metal is 314 kN the max shear stress developed in the materials is a 500 Mpa c 1000 Mpa 3 The b 250 Mpa d None

2 The displacement time graph of a particle executing SHM is as shown in the figure The corresponding force time graph of the particle 3 F A A F

If velocity V of a particle as a function o f position x is given as v a x wher e at t 0 x 0 Then a maximum displacement of particle i sa b maximum displacement of particle i S c It takes time for particle to stop d Time taken to reduce to half of initial

a c 2 2 A d 2 2 mA The peak voltage of an ac supply is 440 V then its rms voltage is a 31 11 V c 41 11 V b 311 1 V d 411 1 V 3 the net power consumed figure is V

A square plate of 0 5m side moves parallel to a second plate with a velocity of 0 2 m s both plates immersed in water If the viscous force is 0 004 N and the coefficient of viscosity is 0 01 poise What is the distance between the plates

An aerostat of mass m starts coming down with a constant acceleration w Determine the ballest mass to be dumped for the aerostat to reach the upward acceleration of the same magnitude The air drag is to be neglected In the arrangement of Fig 10 the

7 If a dipole of dipole moment pi is placed at point 0 y and a point charge at the origin of a coordinate system net electric field at point x x y vanishes If x and y both are positive the coordinate y is equal to a x c 2 5x b 2x d 3x

When a block is placed on a wedge as shown in figure the block starts sliding down and the wedge also start sliding on ground All surfaces are rough The centre of mass of wedge block system will move A leftward and downward C leftward and upwards rough Wedge Block rough B right ward and downward D only downward

One end of a light inextensible string is attached to a ceiling The string passes under a smooth light pulley carrying a weight C and then over a fixed smooth light pulley To the free end of the string is attached a light scale pan in which two weights A and B are placed with A on top of B as shown The portions of the string not in contact with the pulleys are vertical Each of the weights A and B has a mass M and the weight C has a mass 5M If he system is released from rest then which of the following option is are correct A The acceleration of the movable pulley is 13 B The tension in the string between p and p2 is 30mg 13 15mg C The reaction force between the weights A and B is 13 D The reaction force on the pulley p is Download CHE QP PH II PET 4 ADV EX DT 12 10 2020 pdf 30mg 13 Go P1 A P2

A capacitor is charged to a potential 2 points V A dielectric slab of dielectric constant K is introduced between the plates Its energy stored will When potential is constant then increase by O a factor k or when charge is constant then also increase by a factor k When potential is constant then increase by O a factor k or when charge is constant then reduced by a factor 1 k When potential is constant then reduced by O a factor 1 k or when charge is constant then increase by a factor k When potential is constant then reduced by O a factor 1 k or when charge is constant then also reduced by a factor 1 k

A swimmer can swim with speed 15 m sec in still water He wants to reach at point B as shown in figure Speed of river is 10 3 m s width of river is 100 3m If time taken by man to cross the Then 20n is river is 40 n

A 15 foot ladder is resting against a wall 4 The bottom of the ladder is initially 8 feet from the bottom of the wall You start to pull the bottom of the ladder away from the wall at a constant rate of 6 inches per second To the nearest tenth of a foot per second how fast is the top of the ladder moving down the wall after 5 seconds a 0 49 ft sec b 0 60 ft sec c 0 72 f sec d 0 81 ft sec e None of the above

A coil having N turns is wound tightly in the form of a spiral with inner and outer radii a and b respectively When a current I passes through the coil the magnetic field at the centre is 1 3 H NI b HONI b In 2 b a 2 2 NI d MOIN 4 h In b

A current of 2 A is flowing through a wire of length 50 cm If this wire is placed at an angle 60 degree with the direction of the uniform magnetic field of 0 5 milli Tesla then the force will act upon the wire is O4 33 milli newton O 0 433 milli newton O 0 5 milli newton O 5 0 milli newton

A particle is projected from origin in a vertical plane If particle remains above horizontal line AB for 3 seconds and it remains above horizontal line CD for 1 sec Find the separation between the two lines AB and CD in meter g 10 m s

4 30 A simple pendulum of length 1 m has a wooden bob of 30 1 m als Hd con la c 12 x 10 ms mass 1 kg It is struck by a bullet of mass 10 2 kg moving with a speed of 2 x 102 ms 1 The height to which the bob rises before swinging back is Take g 10 ms 1 0 2 m 3 8m Lm 2 0 6 m 4 1 m de us fou de la g 10 ms 1 0 2 m 3 8 m Agni fave 2 0 6 m 4 1 m

138 96 Two different coils have self inductance L 8 ml L 2 mH The current in one coil is increased at constant rate The current in the second coil is als increased at the same rate At a certain instant of time the power given to the two coils is the same At tha time the current the induced voltage and the energ stored in the first coil are i V and W respectively Corresponding values for the second coil at the same instant are 2 V and W respectively Then W W 1 a b W W 8 8

37 38 For any type of oscillatory or viberatory motion 43 which force is necessary 1 Damping force 2 Restoring force 4 Any force 3 External force The equation of motion of a particle executing

A time varying power P 2t is applied on a particle of mass 3kg The change in kinetic energy of the particle in first 4 sec is 043 08J 16 J Market

Germanium and silicon diodes conduct at 0 3 V and 0 7 V respectively In the following figure if Ge diode connections are reversed the Vout changes by magnitude 10 V 0 3 V 0 4 V 0 5 V 0 7 V KF S Ge V R out

7 A transverse wave is travelling along a string from left to right The adjoining figure represents the shape of the string at a given instant At this instant among the following choose the wrong statement A 1 Points D E and F have upwards positive velocity 2 Points A B and H have downwards negative velocity 3 Points C and G have zero velocity

x Threshold wavelength of a metal surface is 5 x 10 7 m When it is illuminated by light of wavelength 3 107m stopping potential is Von what will be stopping potential if wavelength of incident light is doubled O V 2Vo

The teeter toy consists of two identical weights which hang form a peg on drooping arms as shown in the figure The arrangement is unexpectedly stable The toy can be spun or rocked with little danger of toppling over For simplicity consider only rocking motion in the vertical plane For the teeter toy to be stable A L 1 2 B L 1 2 60 a a 60 C L 1 2 D None of these

4 The inward and outward electric flux for a closed surface in units of N m C are respectively 8 x 10 and 4 x 10 Then the total charge inside the surface is where permittivity constant 1 4 x 10 C 2 4 10 C 4x10 3 10 s C

84 If the self inductance of 500 turns coil is 125 mH then the self inductance of the similar coil of 800 turns is a 48 8 mH c 290 mH b 200 mH d 320 mH 93

28 The diagram shows variation of V time where v is in m s t 3 sec 3 A 2 C 1 i 45 C 3 what is the instantaneous acceleration of body at m in t s with respect to B 3 D None of these

The angular velocity of a body is 21 j 4k A torque 7 21 21 2k acts on it The rotational power is 0 14 O 10 0 15 O 16

C 4 S LDTI 29 A particle is thrown upward from ground It experiences a constant resistive force which can produce retardation of 6 m sec What will be the ratio of time of descent to time of ascent g 10 m sec A 2 B 3 C 4 D 1

i 2 2k N C 4 10 10 A metallic solid sphere is placed in a uniform electric field The lines of force follow the path s shown in figure as 1 1 2 2 3 3 4 4

If P E OT AB x x X then the mean position of oscillation is U 1 x 3 X A B B given by relation where A and B are positive constant 2 x 4 x B A 2A B

4 M Spring constant of a spring is calculated using K where T is time period of vertical oscillation when mass T M is hung with the help of spring to rigid support If time of oscillation for 10 oscillation is measured to be 5 0 s and mass M 0 20 kg find possible error in spring constant K

Problem 11 Two semi infinite grounded conducting planes meet at right angles In the region between them there is a point charge q situated as shown in Fig 15 Set up the image configuration and calculate the potential in this region What charges do you need and where should they be located What is the force on q How much work did it take to bring q in from infinity Suppose the planes met at some angle other than 90 would you still be able to solve the problem by the method of images If not for what particular angles does the method work y A b 01 a FIGURE 15 X R S d Vo R d FIGURE 16 X Vo

a 1H b 4H c 0 8 H d 16 H 90 The equivalent inductance of two inductors is 2 4 H when connected in parallel and 10 H when connected in series What is the value of inductances of the individual inductors a 8 H 2H c SH SH b 6 H 4 H d 7 H 3 H

A particle is moving in the xy plane has velocity dx 2t and dy 4 If the particle components dt dt starts from the origin at t 0 magnitude of its displacement at t 2 s is N meter The value of N is