Question

11. An alpha particle (a bare helium nucleus with $q=+2e$) accelerates across a $100V$ potential difference, starting from rest. What is the particle’s kinetic energy in eV when it reaches the negative electrode? This question requires no mathematics beyond what you can do in your head.

Short answer

As, We know

$KE=qV$

So, by putting given values into the equation:

KE= 100x2 =200 eV

Step-by-step solution

Description

The formula for energy in terms of charge and potential difference is

Kinetic energy = potential difference x charge

$KE=qV$

So, by putting given values of charge $q=+2e$

And, Potential difference between the plates $V=100Volt$

into the equation:

$KineticEnergy=2e\times 100V$$=200eV$

So, the particle’s kinetic energy when it reaches the negative electrode is

200eV.