Home
Class 12
PHYSICS
What is the self inductance of a system ...

What is the self inductance of a system of co-axial cables carrying current in opposite directions as shown ? Their radii are a and b respectively and its length `l`.

Text Solution

Verified by Experts

The B between the space of the cables is B `=mu_(0)I/2 pir ` The Ampere.s law tells that B outside the cables is zero as the net current through the amperian loop would be zero . Taking an element of length `l` and thickness dr `d phi` through it is
`dphi=(mu_(0)I)/(2pir)ldrimplies phi =(mu_(0)Il)/(2pi)int_(a)^(b)(1)/(r)dr = (mu_(0)lI)/(2pi)."In" (b)/(a)`
`L=(Phi)/(I)=(mu_(0)l)/(2pi)"In"((b)/(a))`
Promotional Banner

Topper's Solved these Questions

  • ELECTROMAGNETIC INDUCTION

    FIITJEE|Exercise SOLVED PROBLEMS ( SUBJECTIVE)|10 Videos

  • ELECTROMAGNETIC INDUCTION

    FIITJEE|Exercise SOLVED PROBLEMS ( OBJECTIVE)|15 Videos

  • ELASTICITY AND WAVES

    FIITJEE|Exercise Assignment Problems (Objective) Level-II|15 Videos

  • ELECTROMAGNETIC INDUCTION AND AC CURRENT

    FIITJEE|Exercise Example|15 Videos

Similar Questions

Explore conceptually related problems

What is the mutual inducatance of a system of coaxical cables carrying current in opposite directions a sshows in Fig. 4.3. Their radii are a and b , respectively.

An otherwise infinite, straight wire has two concentric loops of radii a and b carrying equal currents in opposite directions as shown in Fig. The magnetic field at the common centre is zero for

What is the mutual inductance of a two-loop system as shown with centre separatiion l ?

The energy stored in an inductor of self inductance L carrying current l, is given by

In a coaxial, straght cable, the central conductor and the outer conductor carry equal currents in opposite directions.The magnetic field is non-zero.

In a coaxial, straight cable, the central conductor and the outer conductor carry equal currents in opposite directions. The magnetic field is zero.

Two identical inductances carry currents that yarr with time according to linear laws, In which of the two inductances is the self-induction emf greater? Will the values or signs of the self-induction emf's change if the currents begin to increase in the opposite direction after they pass through zero (with the linear laws retained in the process)?

The energy stored in an inductor of self-inductance L henry carrying a current of I ampere is

A coil of self inductance 80 mH carries a current of 2A. What is the energy stored in the coil?