An electron is projectd horizontally with a kinetic energy of 10 keV. A magnetic feld of strength `1.0X10^(-7)` T exists in the vertically upward direction. (a)will the electron deflect towards right or towards left of its motion? (b) calculate the sideways deflection of the electrion in travelling through 1m. make appropriate approximations.

Explanation

`KE = 10Kev = 1.6 xx 10 ^(-16) J` ,
` B = 1xx 10 ^(-7) T ` ,
` (a) The eletron will be deflected towards left .
`(b) (1/2 } mv ^2) =KE `rArr V = sqrt (KE xx 2) /(m)` ,
` F= qVB ` rArr accln = qVB/m `
applying s = ut + (1) /(2) at^2`
= (1)/(2) (16 xx 10 ^(-10) xx 1 xx 10^(-7) xx 1 ) (/91 xx 10^(-31))`
By solving we get ,
a = 0.0148 = n1.5 xx 10 ^(-2) cm. `