Advertisements
Advertisements
Question
The force between two parallel current-carrying conductors is F. If the current in each conductor is doubled, then the force between them becomes ______
Options
4F
2F
F
F/4
Solution
The force between two parallel current-carrying conductors is F. If the current in each conductor is doubled, then the force between them becomes 4F.
RELATED QUESTIONS
The electric current flowing in a wire in the direction from B to A is decreasing. Find out the direction of the induced current in the metallic loop kept above the wire as shown.
Define one tesla using the expression for the magnetic force acting on a particle of charge q moving with velocity \[\vec{v}\] in a magnetic field \[\vec{B}\] .
A straight wire carrying an electric current is placed along the axis of a uniformly charged ring. Will there be a magnetic force on the wire if the ring starts rotating about the wire? If yes, in which direction?
Two wires carrying equal currents i each, are placed perpendicular to each other, just avoiding a contact. If one wire is held fixed and the other is free to move under magnetic forces, what kind of motion will result?
According to the right-hand rule, the direction of magnetic induction if the current is directed in an anticlockwise direction is ______
A particle with charge q moves with a velocity v in a direction perpendicular to the directions of uniform electric and magnetic fields, E and B respectively, which are mutually perpendicular to each other. Which one of the following gives the condition for which the particle moves undeflected in its original trajectory?
A proton enters into a magnetic field of induction 1.732 T, with a velocity of 107 m/s at an angle 60° to the field. The force acting on the proton is e = 1.6 × 10-19 C, sin 60° = cos 30° = `sqrt3/2`
For a circular coil of radius R and N turns carrying current I, the magnitude of the magnetic field at a point on its axis at a distance x from its centre is given by,
B = `(μ_0"IR"^2"N")/(2("x"^2 + "R"^2)^(3/2))`
(a) Show that this reduces to the familiar result for field at the centre of the coil.
(b) Consider two parallel co-axial circular coils of equal radius R, and number of turns N, carrying equal currents in the same direction, and separated by a distance R. Show that the field on the axis around the mid-point between the coils is uniform over a distance that is small as compared to R, and is given by, B = `0.72 (μ_0"NI")/"R"` approximately.
[Such an arrangement to produce a nearly uniform magnetic field over a small region is known as Helmholtz coils.]
A charged particle enters an environment of a strong and non-uniform magnetic field varying from point to point both in magnitude and direction, and comes out of it following a complicated trajectory. Would its final speed equal the initial speed if it suffered no collisions with the environment?
An electron emitted by a heated cathode and accelerated through a potential difference of 2.0 kV, enters a region with uniform magnetic field of 0.15 T. Determine the trajectory of the electron if the field (a) is transverse to its initial velocity, (b) makes an angle of 30° with the initial velocity.
A magnetic field set up using Helmholtz coils is uniform in a small region and has a magnitude of 0.75 T. In the same region, a uniform electrostatic field is maintained in a direction normal to the common axis of the coils. A narrow beam of (single species) charged particles all accelerated through 15 kV enters this region in a direction perpendicular to both the axis of the coils and the electrostatic field. If the beam remains undeflected when the electrostatic field is 9.0 × 10–5 V m–1, make a simple guess as to what the beam contains. Why is the answer not unique?
Direction of magnetic force on a positive charge moving in a magnetic field is given by ______.
A deuteron of kinetic energy 50 keV is describing a circular orbit of radius 0.5 metre in a plane perpendicular to the magnetic field B. The kinetic energy of the proton that describes a circular orbit of radius 0.5 metre in the same plane with the same B is ______.
The magnetic moment of a current I carrying circular coil of radius r and number of turns N varies as ______.
A magnetic field exerts no force on
An infinitely long straight conductor carries a current of 5 A as shown. An electron is moving with a speed of 105 m/s parallel to the conductor. The perpendicular distance between the electron and the conductor is 20 cm at an instant. Calculate the magnitude of the force experienced by the electron at that instant.
A circular current loop of magnetic moment M is in an arbitrary orientation in an external magnetic field B. The work done to rotate the loop by 30° about an axis perpendicular to its plane is ______.
Show that a force that does no work must be a velocity dependent force.
A charge particle moves along circular path in a uniform magnetic field in a cyclotron. The kinetic energy of the charge particle increases to 4 times its initial value. What will be the ratio of new radius to the original radius of circular path of the charge particle:
Two long current-carrying conductors are placed parallel to each other at a distance of 8 cm between them. The magnitude of the magnetic field produced at the mid-point between the two conductors due to the current flowing in them is 300µT. The equal current flowing in the two conductors is ______.
Figure shows a square loop. 20 cm on each side in the x-y plane with its centre at the origin. The loop carries a current of 7 A. Above it at y = 0, z = 12 cm is an infinitely long wire parallel to the x axis carrying a current of 10 A. The net force on the loop is ______ × 10-4 N.
A beam of light travelling along X-axis is described by the electric field Ey = 900 sin ω(t - x/c). The ratio of electric force to magnetic force on a charge q moving along Y-axis with a speed of 3 × 107 ms-1 will be : [Given speed of light = 3 × 108 ms-1]
Distinguish between the forces experienced by a moving charge in a uniform electric field and in a uniform magnetic field. (Any two points)
State the expression for the Lorentz force on a charge due to an electric field as well as a magnetic field. Hence discuss the magnetic force on a charged particle which is (i) moving parallel to the magnetic field and (ii) stationary.
State dimensions of magnetic field.
