Question

An electron is projected into uniform transverse electric field of strength 200 with initial velocity 10 power 6 metre per second by what length is electron deflected after it has traveled one centimetre

Answer 1

An electron is projected into uniform transverse electric field of strength 200 N/C with initial velocity 10^6 m/s .

distance covered by electron with speed 10^6 m/s = 1cm or 0.01m

so, time taken = distance covered/speed of electron

= 0.01/10^6 = 10^-8 sec

due to presence of electric field, electron experience electric force so, it is deflected x distance from its position.

acceleration given to electron due to electric field , a = qE/m

charge on electron, q = 1.6× 10^-19C

electric field, E = 200N/C

mass of electron , m = 9.1 × 10^-31 Kg

so, acceleration, a = {1.6 × 10^-19 × 200}/{9.1 × 10^-31}

= (320/9.1) × 10¹² m/s²

=3.516 × 10¹³ m/s²

so, deflection of electron , x = 1/2at²

= 1/2 × 3.516 × 10¹³ × (10^-8)²

= 1/2 × 3.516 × 10¹³ × 10^-16 m

= 1.758 × 10^-3 m

= 1.758 mm