Question

A pair of charged conducting plates produces a uniform field of E_o = 11,020 N/C directed to the right, between the plates. The separation of the plates isL = 35 mm. In Figure, an electron (e = - 1.6 x 10^-19 C; m = 9.1 x 10^-31 kg) is projected from plate A, directly toward plate B, with an initial velocity of v_o =2.1

Answer 1

electric force on electron = 1.6*10^-19 * 11020 = 1.7632 * 10^-15 N

so.. aceeleration of electron = a = -1.7632 * 10^-15 / ( 9.1 * 10^-31 ) = -1.9375824176 * 10^15 m/sec2

so.. let the final velocity be v ..

v^2 = u^2 + 2*a*s

so.. v^2 = ( 2.1 * 10^7)^2 - (2* 1.9375824 * 10^15 * 0.035 )

so.. final velcotiy v = 1.7474817 * 10^7 m/sec

Answer 2

Electrical Work done =change in KE

W=dKE

-eEL =(1/2)mV^2-(1/2)mVo^2

=>V=sqrt[Vo-2eEL/m]

V=sqrt[(2.1*10^7)^2 -2*(1.6*10^-19)*11020*0.035/9.1*10^-31]

V=1.747*10^7 m/s

Answer 3