Basic Physics Questions and Answers

27 A vessel is filled with water and kerosene oil The vessel has a small hole in the bottom Neglecting viscosity if the thickness of water layer is hand kerosene layer is h then the velocity v of flow of water will be density of water is p g cc and that of kerosene is p2 g cc a v 2g h h c v 2g hp h P 20 n M PR P2 P b v d v 2g h P1 P2 h

10 Three forces acting on a body are shown in the figure To have the resultant force only along the y direction the magnitude of the minimum additional force needed is a 0 5 N 3 4 c N b 1 5 N d 3 N 4N Ay 30 1N 60 2 N

Mx and My denote the atomic masses of the parent and the daughter nuclei respectively in a radioactive decay The Q value of decay is Q and that for decay is Q2 If me is mass of an electron then which of the following is correct Q Mx My c

1 of capacity C 1 uF is charged to a potential of 100 V The charging battery is then removed and it is connected to another capacitor of capacity C 2uF One plate of C is earthed as shown in fig The charges on C and C in steady state will be 100 3 C C HE C C 200 3 1x100 2 1 3 1 100 2 50 C 50 C 1 100 c Zero

4 One end of a U tube of uniform bore area A containing mercury is connected to a sunction pump Because of it the level of liquid of density p falls in one limb When the pump is removed the restoring force in the other limb is a 2xp Ag c Apg b xpg d xp Ag X

18 An ohm meter is used 50 B ww www for measuring the resistance of a circuit 15 between two terminals of given circuit all resistances are in ohm 10 What would be the reading of such an instrument used for the circuit between points A and B A and C B and C a 25 20 30 b 20 25 24 c 25 24 9 d 24 9 25 30 www www 8 ww 25 C 14 wwww 3 4 5

Choose the incorrect statement X If multiplication factor K 1 the operation of the reactor is said to be critical Control rods are made out of the neutron absorbing material such as cadmium Water is used as moderator in Apsara reactor BARC Mumbai For thermonuclear fusion reaction temperature of system should be of order of 10 K to overcome the coulombic repulsion

At 23 K the crystal structure transforms from BCC to HCP keeping density same The 0 cubic face in BCC is a 3 42 A and in HCP is 1 53 The lattice constant in HCP a structure is Answer 0 a 2 64 A 0 b 3 16 A 0 c 2 16 A 0 d 2 42 A A 57

Li nucleus has three protons and four neutrons Mass of Li nucleus is 7 016005 amu Mass of Proton is 1 007277 amu and mass of neutron is 1 008665 amu Mass defect of Lithium nucleus in amu is 0 05010

149 Two wires AB and CD carrying currents 20 A and 30 A are kept in vertical plane CD is fixed and AB is free to move in vertical plane In equilibrium wired are at separation 1 0 cm If AB is slightly depressed and then released then find time period of one oscillation A 1 0 cm C 1 0 1 second 3 0 3 second 20 A 30 A B D 2 0 2 second 4 0 32 second

4 33 A linear object AC of length 10 5 the principal axis of a concave mirror of focal lengt 10 cm see figure C is the centre of curvature the mirror The length of the image is UPE hI A 10 cm 1 10 cm ME CS I ITT 2 15 cm K 134 B

Vector A has a magnitude of 2 units and makes an angle of 0 with the positive x axis Vector B has a magnitude of 6 units and makes an an gle of 30 clock wise with the positive y axis Find the magnitude of the resulta nt of Vector A B and also the angle that it makes with Vector A

211 A block of mass 5 kg is kept on horiz surface at rest as shown in the figure A time varying force F is applied on the block The spee of the block at t 10 s is Take g 10 m s 1 0 5 m s 3 2 5 m s 5 kg F 2t 777 0 2 2 1 0 m s 4 5 m s

3 The average depth of Indian Ocean is about 3000 m Bulk modulus of water is 2 2 x 104 N m g 10 m s then fractional compression AV of water V 2014 at the bottom of the Indian Ocean will be a 1 36 C 13 9 b 20 6 d 0 52

When block is at rest it just touches the lower spring So Guddu forgot to connect lower spring with block The time period of oscillation of the block when it is slightly pushed downward and released is 47721 2 2 2 3 T m 2k 2m k S k m 24

20 A tunnel is dug along the diameter of earth and block is released from the surface The speed o the block at the centre of the earth is 5 21 3 1 3 5gR gR 2 4 gR

If two different non axial d orbitals having xz nodal plane form bond by overlapping each other then internuclear axis will be 1 x 2 y 3 Z 4 They do not form bond

6 If a ladder weighing 250 N is placed against a smooth vertical wall having coefficient of friction 0 3 then what is the maximum force of friction available at the point of contact between the ladder and the floor M 0 3 1 75 N 2 50 N 3 35 N 4 25 N 25kg 20

Resistivity of semiconductor belongs in range 10 5 Qm to 10 Qm At 0 C semiconductor behaves as conductor Eg carbon Eg silicon

Tw 6 kg rest one over the other on a smooth horizontal plane The coefficient of static and dynamic friction between A and B is the same and equal to 0 3 The maximum horizontal force F that can be applied to B in order that both A and B do not have any relative motion is 0 3 F 1 30 N 3 12 kgf A B 4 kg 6 kg 2 30 kgf 4 12 N 1

c 3 45 x 10 Pa s mb a s d 3 45 x 102 Pa s 6 Three liquids of densities p P and p with p P P3 having the same value of surface tension T rise to the same height in three identical capillaries The angles of contact obey 2016 II a T I 0 0 0 b 0 0 0 2 Pa Na 2 TU c 0 0 0 0 d 0 0 0 0 C

The magnetic field energy stored by an inductor connected to an ac circuit takes 2 5 ms for changing between maximum and minimum values The frequency of the a source is A 400 Hz B 200 Hz C 100 Hz D 50 Hz

70C charge is distributed uniformly on a line joining point A 2 5 and point B 5 5 Consider another point C 14 17 All the distances are in m choose correct option s A x component of electric field at point C 7 240 7 240 EO C Electric field is directed at angle tan 7 from x axis B y component of electric field at point C D Electric field is directed at angle 45 from x axis 2

Suppose that a day s production of 850 manufactured parts contains 100 parts that do not conform to customer requirements Two parts are selected at random in succession and without replacement from the batch Let the random variable X equal the number of nonconforming parts in the sample Then the cumulative distribution function of X is OF 0 0 846 F 1 0 993 F 2 1 OF 0 0 577 F 1 0 736 F 2 1 OF 0 0 879 F 1 0 996 F 2 1 OF 0 0 778 F 1 0 986 F 2 1

View In English A pump is used to deliver water at a certain rate from a given pipe To obtain water 2 times in the same time the power of the pump has to be made 1 2 3 2 times 4 times 8 times 16 times Correct Answer 3 Status unattempted Add to Bookmark List Using woo

charges Q centres is R a E E E dv All space 1 If E and E are electric field vectors due to two spheres at any point then what is value of KQ Q Distance between their E E 2 KQ KQ2 22

Q No 36 View In English A ball after falling from a height of 10 m strikes the roof of a lift which is descending down with a velocity of 1 m s The recoil velocity of the ball will be 1 2 3 4 8 m s 11 m s 12 m s 15 m s Correct Answer 3 Status unattempted Add to Bookmark List D A pump is used to deliver water at a certain rate from a given pipe To obt

Determine the number of nuclei that will be decayed upto one average life of radioactive material No Initial number of nuclei 2 No 1 1 1 3 No e No xe 2 4 No 1 e

In an intrinsic semiconductor the energy gap Eg is 1 2eV Its hole mobility is much smaller than electron mobility and independent of temperature What is the ratio between conductivity at 600K and that at 300K Assume that the temperature dependence of intrinsic carrier concentration nu is given by E 2KBT 1 no exp 1 1 01 x 106 1 2 1 09 x 10 1 3 1 1 4 1 2 where no is a constant

No 33 1 2 3 4 View in English A sphere of radius 10 cm and density 500 kg m is under water of density 1000 kg m3 The acceleration of the sphere is 9 80 m s2 upward Viscosity of water is 10 centipoise If g 9 81 m s2 the velocity of the sphere is Correct Answer 3 tatus unattemptod Peor Stat x Unattemptod 423 Corroct 35 7 Incorrect 22 0 Complete Question Content 9 m s 10 m s 11 m s 12 m s Clos D

A passes through the centre of a sphere of radius R as shown in figure Then the electric flux through the n R sphere is E R 2 Find n Answer 0 01 02 03 04 05 06 07

View In English Two conducting spherical shells of radii R and 2R carry charges Q and 3Q respectively How much charge will flow into the earth if the inner sholl grounded 3Q 1 2 3 NANONOO Correct Answer 2 Status unattempted Rookroauktion 2R 2 1 R A pump is used to deliver water at a certain rate from a given pipe To obt Right Answor 31 Your Answer AN 2

A particle of mass m is moving with constant velocity v parallel to the x axis as shown in the figure Its angular momentum about origin O is YA 1 mvb O a EX m X 2 mva

The spherical symmetric potential in which a particle is moving is V r Br where B is a positive constant what is the relationship between the expectation value of kinetic and potential energy of particle in stationary state is a T U 3 5 d T 5 U Acti Go to

Q 12 Oscillating metallic pendulum in a uniform magnetic field directed perpendicular to the plane of oscillation a slows down b becomes faster mmmmmmmmmmmmmmmm

5 A projectile of mass m is thrown with speed u at an angle 0 from the horizontal The moment of the gravitational force on the projectile about point of projection t time after the projection is 1 mgut 3 mautcose 2 mgusinot 4 mautanet

View In English Assuming that 200 MeV of energy is released per fission of 920235 atom Find the number of fission per second required to release 1 kW power 1 2 3 125 x 10 3 3 125 x 10 4 3 125 x 1015 3 125 x 1016 Correct Answer 1 Status unattempted Add to Bookmark List gy 13 4 Assuming that 200 MeV of energy is released per fission of 920235 atom Fin Right Answer 11 Your Answer Difficulty Level medium Topic physics modom physics 4 DIA

P103 A uniform magnetic field B Bot fills a cylindrical volume of radius R then the emf induced in the rod AB is A A Bol R C Bol R 2 X X X 20 X X B 1 4 B BolR D BOR R

A circular beam of light having a diameter 4 cm falls on a plane glass slab at angle of incidence 60 If refractive index of the material of slab is 3 H 2 then diameter of the refracted beam is SA M Sian 1 10 2 cm 2 3 8 cm 2 2 cm 1x52x S 3 4 4 3 cm

Exhaustion stage of stress reaction In the Alarm stage of stress reaction In the relapse stage of stress reaction In the Fight or Flight stage of stress reaction

Example 6 14 Two trains each of length 100 m are running on parallel tracks One overtakes the other in 20 seconds and one crosses the other in 10 seconds Calculate the velocity of each train

A balloon leaves the earth at point A and rises vertically at uniform speed At the end of 2 minutes Sabari finds the angular elevation of the balloon as 45 degrees If the point at which Sabari is standing is 150 m away from point A then what is the speed of the balloon a 1 25 m s b 1 33 m s c 1 5 m s d 1 6 m s

n ideal gas undergoes through a process as shown in the figure At state C 5Vc VA The pressure of ne gas at C is 1 106 N m Find the value of n P4 10 N m 8 6 4 2 D C 100 K B A 700 K T 3

1 An infinitely long line charge has a linear charge density A rod of length L and mass m pivoted a its centre carries charge of linear density 2 on upper half and on lower half as shown in the figure The initial angular acceleration of rod will be 1 2 m r 8 R 2 3 2 TE

4 All of these 130 In the given figure a force of 24 N acts on the upper block then find friction acting on 4 kg block g 10 m s 24 N 400 1 20 N 3 12 N 4 kg u 0 5 8 kg Smooth 2 16 N 4 14 5 N 6 5 470 20

The length of a metal plate was measured using a Vernier callipers of least count 0 01 cm The measurement made were 4 11 cm 4 13 cm 4 21 cm and 4 09 cm Find the mean length the mean absolute error relative error and the percentage error in the measurement of length Ans i 4 135 cm ii 0 0375 cm iii 9 068 10 iv 0 906 19 19 The length of a metal plate was measure d using a Vernier callipers of least count 0 01 cm The measurement made were 4 11 cm 4 13 cm 4 21 cm and 4 09 cm Find the mean l ength the mean absolute error relative erro r and the percentage error in the measureme nt of length Ans i 4 135 cm ii 0 0375 cm iii 9 068x10 3 iv 0 906

RT 95 A gas obeying the equation of state PV undergoes a hypothetical reversible process described by the equation PV5 3 exp PV E a approaches a constant value b is proportional to T c is proportional to T1 2 d is proportional to T C where c and E are dimensioned constants Then for this process the thermal compressibility at high temperature

Electromagnetic waves of wavelength 500 nm are incident on a YDSE apparatus Both slits are o same width Here d 3 mm D 2 m Intensity at central maxima is 1 W mr what is the intensity in W m at a point 1mm above maxima of order 1

A steel scale measures the length of a copper wire as 80 0 cm when both are at 20 C the calibration temperature for scale What would be the scale read for the length of the wire when both are at 40 C Given asted 11x10 6 per C and acopper 17x10 6 per C a 80 0096 cm b 80 0272 cm c 1cm d 25 2 cm

94 A solid cube of wood of side 2a and mass M is resting on a horizontal surface as shown in the figure The cube is free to rotate about a fixed axis AB A bullet of mass m M and speed v is shot horizontally at the face opposite to ABCD at a height 4a 3 from the surface to impart the cube an angular speed It strike the face and embeds in the cube Then o is close to note the moment of inertia of the cube about an axis perpendicular to the face and passing through the center of mass is 2Ma 3 a Mv ma D A B b Mv 2ma