Find the charge on a piece of dust

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AI Thread Summary
To find the charge on a piece of dust in an electric field, the weight of the dust must be equated to the electric force acting on it. The weight is calculated using the mass (1.6 g) multiplied by gravitational acceleration (9.81 m/s²). The electric force is determined by multiplying the charge (q) by the electric field strength (511 N/C). Setting the two forces equal allows for solving the charge, and subsequently, the number of excess electrons can be calculated. Understanding the distinction between mass and force is crucial for solving the problem correctly.
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Homework Statement



A small piece of dust of mass m = 1.6 g travels horizontally through an electric air cleaner in which the electric field is 511 N/C. The electric force on the particle is equal to the weight of the particle.
What is the charge on the dust particle?
If this charge is provided by an excess of electrons, how many electrons does that correspond to?

Homework Equations



I know i have to solve for q and that my mass is the same as my force..but i have no idea where to even start. any help is appreciated!

The Attempt at a Solution

 
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Mass is not force.

Two forces involved here. Name them and compare their magnitudes (sizes).
 
well the reason why i think the mass and force are equal is because it said so in the problem.
 
No it did not.

Read it again. You seem to be making a fundamental error in a specific concept.
 
is there any way you can help me set it up? if i can get a beginning equation down i can do the rest of it.
 
Look at my first reply and answer the questions I asked.

I'll repeat, there are two forces involved (mass is still not a force; here on earth, what do you multiply mass with to get a force, and what is that force commonly known as?)
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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