Question

A particle of charge 5e is placed in an electric field of 20 volts. Calculate it's kinetic energy in ev, J, kJ/mole.​

Answer 1

Work done by Electric field = kinetic energy

5 × 1.6 × 10^-19 × 20

16 × 10^-18 J or. 100 ev

Answer 2

Given :

The charge of a particle = q = 5 e v  

The magnitude of electric field = E = 20 volt

To Find :

The kinetic energy of particle in kJ/mole  

Solution :

Since , kinetic energy = work done by particle

∵ 1 ev = 96.485  kJ/mole

∴  5 ev =  5 ×  96.485  kJ/mole  = 482.425 kJ/mole

And  Work done by particle = charge × electric field

Or,                                          = 5 × 482.425 × 20  kJ/mole      

Or,                                           = 48242.5 kJ/mole    

∴       Work done by particle = 48242.5 kJ/mole  

Now,

As  kinetic energy = work done by particle

So,  kinetic energy = work done by particle = 48242.5 kJ/mole  

∴    kinetic energy =  48242.5 kJ/mole  

Hence, The kinetic energy of particle is 48242.5 kJ/mole   Answer