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A long straight wire carries a current o...

A long straight wire carries a current of 10 A. An electron moving at `10^7 ms^(-1)` is `2.0 cm` from the wire. Find the force acting on the electron if its velocity is directed towards the wire.

Text Solution

Verified by Experts

`I = 10A`
`v = 10^7 ms^(-1)`
`r = 2 cm = 2 xx 10^(-2) m`
Magnetic field due to long straight currect carrying conductor is given by
`B = (mu_0)/(4pi) (2I)/(r)`
`implies B = 10^(-7) xx (2 xx 10)/(2 xx 10^(-2))`
`implies B = 1 xx 10^(-4) T`
Magnetic field is perpendicular to plane and directed downward at a distance 2.0 cm from the wire.
Force acting on the electron = `F= Bev sin theta`
`F = 1.6 xx 10^(-19) xx 1 xx 10^(-4) xx 10^7 xx sin 90^@`
`F = 1.6 xx 10^(-16) N`
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