Question

fields/prob23 7 html x (cm) +173.33 18.33 +100.00 +50.00 [play [pa use step>> reset Please wait for the animation to completely load An electron is shot through a region of constant electric field (time is given in μsec [104 s] and position is given in centimeters Rest a. Which vector most closely shows the direction of the electric field? A. b. What is the magnitude of the electric field?

Answer 1

The electron has final velocity in the direction of B

force on an an electron is opposite to the direction of the electric field as it has -ve charge.

The direction of the field is along F vector.

Force on th electron F = Ee ; e is the field and e is the charge on electron

acceleration of the electron a = F/m_e = Ee/m_e ; m - mass of electron

let t is time of flight

displacement s = at²/2 = Eet²/2m_e

field E = 2sm_e/et²   

displacement in x = 163.35 cm

time of flight t = 4.6 -1.25 = 3.35 us

E = 2*163.35E-2 * 9.0E-31 /( 1.6E-19 * (3.35E-6)² )

= 1.6375 N/C

This filed is the x-component which caused acceleration in x-direction

we take file is making -45^o with x-axis

actual field = 1.414 * 1.6375 = 2.316 N/C