I need help on a few questions.(adsbygoogle = window.adsbygoogle || []).push({});

1.An alpha particle has a positive charge of 2e and a mass of 6.6 x 10^-27 kg. With what velocity would the particle reach the negative plate of a parallel plate apparatus with a potential difference of 2.0 x 10^3 V.

a)if it started from rest at the positive plate.

b)if it started from rest at a point halfway between the plates.

I got the answer for a, it 4.4 x 10^5 m/s. But i dont know how to do b.

2. An electron is accelerated through a uniform electric field of magnitude 2.5 x 10^2 N/C with an initial speed of 1.2 x 10^6 m/s parallel to the electric field.

a)Calculate the speed of the electron after it has travelled 2.5 cm in the field.

I dont know how to do this one at all.

3. Two electrons are fired at 3.5 x 10^6 m/s directly at each other.

a)Calculate the smallest possible between the two electrons.

I tried do Ee=Ek but that didnt work i kept getting the wrong answer. So can anyone please help me.

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# Homework Help: Electric fields and parallel plates

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