An electron is projected into a uniform electric field E = (1000 N/C)i with an initial velocity (2.00* 10^6m/s)i in the direction of the field. How far the electron travel before it is brought momentarily to rest?

2 answers

  1. the field is horizontal

  2. retarding force = E e = m a where m is electron mass and e is electron charge so
    a = Ee/m
    constant Force --- > constant de acceleration, just like gravity
    if you throw something up with speed Vi
    F = -m g = - m a
    v = Vi - g t, when v = 0, t = Vi/g
    x = Vi t - (1/2) g t^2
    x = Vi^2/g - (1/2) g Vi^2/g^2 = (1/2) Vi^2/g
    here instead of g we have for acceleration E e/m
    so
    x = (1/2) Vi^2 [ m / Ee ]

Answer this Question

Still need help?

You can ask a new question or browse existing questions.