1.

A long straight non-conducting string carriers a charge density of `40 muC//m`. It is pulled along its length at a speed of `300 m//sec`. What is the magnetic field at a normal distance of `5 mm` from the moving string?A. `B=4.8xx10^(-7) tesla`B. `B=3.2xx10^(-7) tesla`C. `B=2.5xx10^(-7) tesla`D. `B=5xx10^(-7) tesla`

Answer» Correct Answer - A
The moving straight behaves like a current,
`i=(40xx10^(-6)C//m)(300m//sec)`
`=1.2xx10^(-2) ampere`
Then `B=(mu_(0)i)/(2pir)=(2xx10^(-7)xx1.2xx10^(-2))/(0.005)`
`=4.8xx10^(-7) tesla`


Discussion

No Comment Found

Related InterviewSolutions