Magnetic Field due to current Questions and Answers

There are two coils A and B as shown in figure coil B is fixed A current starts flowing in B as shown when A moves away from B and stops when A stops moving We can refer that A B O There is a constant current in the counter clockwise direction in A There is a constant current in the clockwise direction in A There is a varying current in A in counter clockwise direction There is no current in A

A particle of mass m and charge q moving with velocity V enters Region II normal to the boundary as shown in the figure Region II has a uniform magnetic field B perpendicular to the plane of the paper The length of the Region II is l Choose the correct choice s Figure 0 Region I V A The particle enters Region III only if its velocity V qCB m B The particle enters Region III only if its velocity V qCB m Region II Region III XXXXX XXXXX XXXXX XXXXXX l C Path length of the particle in Region II is maximum when velocity V qCB D Time spent in Region II is same for any velocity V as long as the particle returns to Region I m

horizontally and is free to rotate about its axis as shown in the figure A strong magnet is held vertically at a point above the disc away from its axis On revolving the magnet about the axis of the disc the disc will the figure is schematic and not drawn to scale S N a rotate in the direction opposite to the direction of magnet s motion h rotato in the direction on the direction of magno notion

4 58 Find the force experienced by a pole of strength 100Am at a distance of 20cm from a short bar magnet of length 5cm and pole strength of 200Am on its axial line Ans 2 5 x 10 2N

Assertion A The Coulomb force between two points charges depend upon the dielectric constant of the intervening medium Reason R Coulomb s force varies inversely with the dielectric constant of medium A A B B C C

4 41 A long straight wire along the z axis carries a current I in the negative z direction The magnetic vector field B at a point having coordinates x y in the z 0 plane is A C Mol yi xj 2n x y Mol xj yi 2 x y B D Mol x yj 2 x y Mol xi yj 2 x y

A long straight wire carrying a constant current creates a magnetic field around it The magnetic field strength is measured with a magnetic field sensor at varying distances from the wire while the current is kept constant Which of the following indicates a graph that will have a constant positive slope and the Maxwell equation most closely related to the graph A B D E A graph of the magnitude of the magnetic field as a function of the current This is related to Faraday s law A graph of the magnitude of the magnetic field as a function of distance from the center of the wire This is related to Faraday s law A graph of the magnitude of the magnetic field as a function of distance from the center of the wire This is related to Ampere s law A graph of the magnitude of the magnetic field as a function of the inverse of the distance from the center of the wire This is related to Faraday s law A graph of the magnitude of the magnetic field as a function of the inverse of the distance from the center of the wire This is related to Ampere s law

When the two magnets are moved perpendicular to plane of coil as shown then ares a emfis induced b Induced current flows from A to Balong the coil when A and B are connected through resistor c Electrons flow from B to A along the coil d Hence plate A will become negatively charged and plate B becomes positively charged

Current i is being carried by an infinite wire passing through origin along the direction Find magnetic field due to the wire at point 1 m 0 0 3 1 1 2x T T 4x 2 4 H i 2 T 3 Hol T 2 2

Two parallel long straight conductors are placed perpendicular to a metre scale in same plane at the 2 cm and 6 cm marks They carry current and 31 respectively in same direction The net magnetic field due to them will be zero At the 8 cm mark At the 1 cm mark At the 5 cm mark At the 3 cm mark

of 10 4N m is required to hold a magnet at 90 with the horizontal component of the earth s magnetic field Torque required to hold it at 30 is 0 4Nm 4Nm thim

A cyclotron s oscillator frequency is 10 MHz If the radius of its dees is 60 cm what is the kinetic energy of the proton beam produced by the accelerator Given e 1 60 10 19 C m 1 67 x 10 27 kg 1 MeV 1 6 10 13 J O 3 421 MeV O 4 421 MeV O 5 421 MeV

A current carrying coil is subjected to a uniform magnetic field The coil will orient so that its plan becomes O O inclined at any arbitrary angle to the magnetic field O parallel to the magnetic field O perpendicular to the magnetic field inclined at 45 to the magnetic field

Statement 1 The magnetic field on the axis of a solenoid is non uniform Statement 2 When a charged particle is projected along the axis of current carrying solenoid the path of the particle is not changed O O O O Statement 1 is True Statement 2 is True Statement 2 is a correct explanation for Statement 1 Statement 1 is True Statement 2 is True Statement 2 is NOT a correct explanation for Statement 1 Statement 1 is True Statement 2 is False Both statements are False

A particle of mass m and charge q enters a region of magnetic field with speed v as shown in the figure If collision of particle with wall is elastic then time after which velocity of particle becomes antiparallel to its initial velocity is d X X m q V t 0 X X 1 X x Y m x X X x X x x x x m x 4 2q B x 3 2 x X B x x x x X x no magnetick field X X X X d 2 M 4qB m mv 2qB wall x 2 4 2 11

A hollow cylindrical wire of inner radius a and outer radiu b carries current i as shown in figure If the current density is uniform across its cross section the magnetic field at point P such that a r b is b a Hoi r a 2 b a r Moir 2 b a Hoiab 27 b a r