Advertisements
Advertisements
प्रश्न
Using Ampere’s circuital law, obtain an expression for magnetic flux density ‘B’ at a point near an infinitely long and straight conductor, carrying a current I.
Advertisements
उत्तर
Consider a point P at a distance from a straight infinity long wire (conductor) carrying a current I in free space.
Because of the axial symmetry about the straight wire, the magnetic induction has the same magnitude B at all points on a circle in a transverse plane and centred on the wire. We therefore choose an Amperian loop, a circle of radius r centred on the wire with its plane perpendicular to the wire.
`vec"B"` is everywhere tangential to the circular Amperian loop.
Angle θ = 0° (between `vec"B" and vec"dl"`) at all points on the loop.
`oint vec"B" * vec"dl" = oint "Bdl" = "B" oint "dl" = "B"(2pi"r")`
`therefore oint vec"B" * vec"dl" = mu_0"I"`
Where `mu_0` is the permeability of free space.
B = `(mu_0 "I")/(2pi"r")`
APPEARS IN
संबंधित प्रश्न
State Ampere’s circuital law.
State Ampere’s circuital law.
Using Ampere’s circuital law, obtain the expression for the magnetic field due to a long solenoid at a point inside the solenoid on its axis ?
Consider the situation described in the previous problem. Suppose the current i enters the loop at the points A and leaves it at the point B. Find the magnetic field at the centre of the loop.
A thin but long, hollow, cylindrical tube of radius r carries i along its length. Find the magnitude of the magnetic field at a distance r/2 from the surface (a) inside the tube (b) outside the tube.
Two large metal sheets carry currents as shown in figure. The current through a strip of width dl is Kdl where K is a constant. Find the magnetic field at the points P, Q and R.
Ampere’s circuital law is given by _______.
A thick current carrying cable of radius ‘R’ carries current ‘I’ uniformly distributed across its cross-section. The variation of magnetic field B(r) due to the cable with the distance ‘r’ from the axis of the cable is represented by:
