Question

A coil of 2000 turns is wound uniformly over
nonmagnetic ring of mean circumference of 80 cm and
cross sectional area of 0.6 sq.cm. If the current through through the coil is 2A, calculate, i) Magnetic force
ii) Reluctance iii) Total flux and iv) Flux density.

Answer 1

Answer:

To find the flux of field there is a formula

B=μ *N *I/(2*π*r)

r- the mean radius. if the mean circumference s=0.6 m, the the mean radius

r=s/(2*π)=0.1

the value of munot is constant: μ=4(3.142)x10-7 web/amp m

Hence we have

B=4*3.142x10-7 * 200*4/(2*3.142*0.1)

B=1.6x10-3 weber/m2 or tesla

So we get magnetic field

For finding the magnetic flux density there is a formula

magnetic flux=magnetic field * Area

magnetic flux=1.6x10-3 * 0.5x10-3

magnetic flux=0.8x10-6 webers

Now flux density

flux density=magnetic flux/area

flux density=1.6x10-3 web/m2