An electron is released from rest at the negative plate of a parallel plate capacitor. the charge per unit area on each plate is = 2.1 × 10^-7 c/m^2, and the plates are separated by a distance of 1.2 × 10^-2 m. how fast is the electron moving just before it reaches the positive plate?

Explanation:

An electron is released from rest, u = 0

We know that charge per unit area is called the surface charge density i.e.

Distance between the plates,

Let E is the electric field,

E = 23728.81 N/C

Now,

Let v is the speed of the electron just before it reaches the positive plate. So, third equation of motion becomes :

Hence, this is the required solution.

the answer is 12 as i may remember

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