A particle of mass m and charge q is thrown at a speed u against a uniform electric field E. How much distance will it travel before coming to momentary rest?


Given:
Mass of the particle: m
Charge of the particle: q
initial velocity of the particle when thrown : u
Uniform electric field : E
Formula used:
When a charge q moves in an uniform electric field E, it experiences an electric force F.
F=qE
But this particle is thrown against the electric field, hence the force experience would be negative.
F=-qE
According to Newton’s Second Law:
F=ma
Where a is the acceleration and m is the mass of the body.
Thus,
We will be using one of the equations of motion.
Here, v is the final velocity of the particle, u is the initial velocity, a is the acceleration and s is the displacement.
Since particle comes to rest, final velocity: v=0
Thus,


Hence, the particle will travel units before coming to rest.


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