Question

To study the properties of various particles, you can accelerate the particles with electric fields. A positron is a particle with the same mass as an electron but the opposite charge (+e). If a positron is accelerated by a constant electric field of magnitude 293 N/C, find the following.

(a) Find the acceleration of the positron.

_________m/s2

(b) Find the positron's speed after 8.45 *10^-9 s. Assume that the positron started from rest.

_____m/s

Answer 1

(a)

Force on charge e in presence of electric field E is

By Newton's second law of motion, the acceleration of the positron is

where m=9.11x10^-31kg is the mass of the positron which is equal to the mass of electron.

Substituting values

(b)

Initial speed of the proton is zero. u=0

The acceleration is constant, the motion of the electron is governed by kinematics equation for uniformly accelerated motion. To find the velocity at time t