Saved Bookmarks
| 1. |
A straight wire of length pi//2 m is bent into a circular shape. O is the center of the circle formed and P is a point on its axis which is at a distance 3 times the radius from O. A current of 1 A is passed throughit. Calculate the magnitude of the magnetic field at the points O and P. |
|
Answer» Solution :Given : Circumference `C=PI/2` m I =IAn=1 Circumference of a circle =`2pir` `cancelpi/2=2cancelpir RARR r=1/4m` r=0.25 m We known that `B=(mu_0 2 pi n Ir^2)/(4PI(r^2+x^2)^(3//2))` At `THETA` , x=0 `B=(mu_02pinIr^(cancel2))/(4pir^(cancel31))` `B=(mu_02pinI)/(4pir)=mu_0/(4pi)(2pinI)/(r)=10^(-7)XX(2xx3.14xx1xx1)/0.25` `B=25.12xx10^(-7)` T At `Px=3r=3xx0.25=0.75` `B=mu_0/(4pi)(2pinIr^2)/((r^2+x^2)^(3//2))=10^(-7)xx(2xx3.14xx1xx1xx(0.25)^2)/([(0.25)^2 +(0.75)^2]^(3//2))` `B=(0.3925xx10^(-7))/([0.062+0.562]^(3//2))=(0.3925xx10^(-7))/((0.624)^(3//2)) = (0.3925xx10^(-7))/((0.624)sqrt(0.625))=(0.3925xx10^(-7))/0.4933` `B=0.795xx10^(-7)` T. |
|