An electron (with charge `1. 6 xx 10 ^(-19) C)` moving at right angles to a uniform magnetic field completes a circular orbit in `10 ^(-6) sec.` Calculate the vlaue of magnetic field. Given mass of electron `= 9 xx 10 ^(-31) kg .`

Explanation

We know that the time taken by an electron to completes a circular orbit is given by
`T = ( 2 pi m )/( q B) or , B = ( 2 pi m )/( q T)`
Here, `m = 9 xx 10 ^(-31) kg, q = 1. 6 xx 10 ^(-19) C, T = 10 ^(-6) sec`
`therefore B = 2 xx (22)/(7) xx ( 9 xx 10 ^(-31))/( . 6 xx 10 ^(-19) xx 10 ^(-6))`
`implies T = (396 )/(112) xx 10 ^(-5) T = 2. 57 xx 10 ^(-5) T`