Force Experienced by an Electron in an Electric Field

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An electron in an electric field of strength 300 N/C experiences a force calculated using the formula F = qE, where q is the charge of the electron (1.6 x 10^-19 C). The correct force is approximately 4.8 x 10^-17 N, indicating that the provided answer choices are incorrect. For a particle with a mass of 0.005 kg and a charge of +4.0 µC, the electric field strength needed to balance its weight is derived from E = mg/q, resulting in approximately 1.225 x 10^4 N/C, which also does not match the listed options. The discussion highlights confusion over the calculations and the accuracy of the provided questions. Accurate application of the formulas is essential for resolving these physics problems.
Soaring Crane
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An electron is placed in an electric field of strength 300 N/C. What is the magnitude of the force the electron experiences?
1.6x10^13 N
2.4x10^13 N
3.2x10^14 N
4.8x10^14 N
6.4x10^14 N

A particle of mass 0.005 kg is given a charge of +4.0 µC and is placed in an electrical field that is directed antiparallel to the Earth's gravitational field. What is the field strength, expressed in N/C, if it balances the weight of the particle?
1.6 x10^6
2.4 x10^6
3.2 x10^6
4.4 x10^6
4.7 x10^6

Wen I tried to do these questions, I did not even come close to the figure in bold. I thought F = Eq or F = mg/q would be sufficient enough, but I guess not. Can anyone explain how to arrive at each answer?

Thanks.
 
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F = Eq is the correct equation to use for the first part, but all those answers listed are wrong.
q is the charge of an electron = 1.6 * 10^-19 C,
Just look at the exponents. You would have to have an E in the order of 10^33 N/C in order to come anywhere near those numbers. Are you sure you copied the question correctly?

For the second, I think you mean E = mg/q not F = mg/q. Again, all the choices are wrong? Where did you get these questions?
 
Soaring Crane said:
An electron is placed in an electric field of strength 300 N/C. What is the magnitude of the force the electron experiences?
1.6x10^13 N
2.4x10^13 N
3.2x10^14 N
4.8x10^14 N
6.4x10^14 N
None of these answers are even close to being right. The force is qE. If E is 300 and q is 1.6e-19 Coulomb, qE = 4.8e-17 N.

A particle of mass 0.005 kg is given a charge of +4.0 µC and is placed in an electrical field that is directed antiparallel to the Earth's gravitational field. What is the field strength, expressed in N/C, if it balances the weight of the particle?
1.6 x10^6
2.4 x10^6
3.2 x10^6
4.4 x10^6
4.7 x10^6
Again: F = qE, but in this case F also = mg, so qE = mg; E = mg/q

Plugging in the numbers, E = 5e-3*9.8/4e-6 = 1.225 e4 N/C Again none of the answers fit.

Where did you get these questions?

AM
 
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