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Electrostatic force

How do you find electrostatic force of a single charge in a uniform electric field given charge, distance (d), and kinetic energy, the only equation I can think of is F=EQ???
Original post by Jimmy20002012
How do you find electrostatic force of a single charge in a uniform electric field given charge, distance (d), and kinetic energy, the only equation I can think of is F=EQ???



Could you please provide us with the complete question in context.

I'm not sure why you have mentioned kinetic energy here.

The force (acting on a unit positive charge) at a distance r from a charge Q is given by the standard formula

F=(14πϵ0)Qr2F = (\frac{1}{4 \pi \epsilon_0})\frac{Q}{r^2}

If this is not what you mean please provide more information.
Sorry here is the complete question:

Figure 1 shows a negative ion which has a charge of -3e and is free to move in a uniform electric field. When the ion is accelerated by the field through the distance of 63mm parallel to the field lines it's kinetic energy increases by 4.0 x 10^-16J.

Calculate the magnitude of the electrostatic force acting on the ion?

Not sure what to do if your given kinetic energy, it just seems confusing, the sia gram just shows field lines and the point charge of -3e

Thanks
Original post by Jimmy20002012
Sorry here is the complete question:

Figure 1 shows a negative ion which has a charge of -3e and is free to move in a uniform electric field. When the ion is accelerated by the field through the distance of 63mm parallel to the field lines it's kinetic energy increases by 4.0 x 10^-16J.

Calculate the magnitude of the electrostatic force acting on the ion?

Not sure what to do if your given kinetic energy, it just seems confusing, the sia gram just shows field lines and the point charge of -3e

Thanks


Work done by a force = increase in kinetic energy

Work done = force x distance
You are given the distance.

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