Answer:
Option C is the untrue statement.
Answer:

Explanation:
The change in electrical potential energy of a charged particle moving through a potential difference is given by

where
q is the magnitude of the charge of the particle
is the potential difference
In this problem:
- the charge of the particle is 3.00 elementary charges, so

- the potential difference is

So, the change in electrical potential energy is

Answer:
Magnetic force is equal to 
Explanation:
We have given electron is accelerated with a potential difference of 81700 volt.
Magnetic field B = 0.508 T
Angle between magnetic field and velocity 
Mass of electron 
Charge on electron 
By energy conservation.



Magnetic force on electron



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