A dust particle through an electric field

AI Thread Summary
A dust particle with a mass of 3.8 micrograms travels through an electric field of 526 N/C, where the electric force equals its weight. The charge on the dust particle is calculated using the formula q=F/E, resulting in approximately 7.079 x 10^-11 C. The discussion emphasizes the importance of significant figures and units in calculations. Participants encourage clarity in questions and reasoning to facilitate better assistance. Overall, the focus is on ensuring accurate calculations and effective communication in problem-solving.
baker265
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Homework Statement


A small piece of dust of mass m = 3.8 mu or micro g (micrograms) travels through an electric air cleaner in which the electric field is 526 N/C. The electric force on the dust particle is equal to the weight of the particle.

(a) What is the charge on the dust particle?


Homework Equations


F=ma
q=F/E


The Attempt at a Solution


((3.8*10^-9)*9.81)/526=7.079*10^-11
 
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baker265 said:

Homework Statement


A small piece of dust of mass m = 3.8 mu or micro g (micrograms) travels through an electric air cleaner in which the electric field is 526 N/C. The electric force on the dust particle is equal to the weight of the particle.

(a) What is the charge on the dust particle?


Homework Equations


F=ma
q=F/E


The Attempt at a Solution


((3.8*10^-9)*9.81)/526=7.079*10^-11

Two things: 1) no. of sig figs you can give the result to and 2) lack of units. Other than that, looks right. Is there a question?
 
Okay, thanks! I just wanted to make sure I was doing it correctly.
 
What he said.
Always, please, show your reasoning and working.
Always ask a specific question so we don't have to guess what you want.

Oh... welcome to PF BTW.
 
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