How Does Electric Field Magnitude Make a Charged Ball Float?

AI Thread Summary
To determine the electric field magnitude required to make a charged ball float, one must balance the gravitational force acting on the ball with the electric force generated by the electric field. The gravitational force can be calculated using the ball's mass and the acceleration due to gravity. The electric force is expressed as Felectric = E * q, where E is the electric field and q is the charge of the ball. By setting the gravitational force equal to the electric force (Fgrav = Felectric), the necessary electric field can be derived using the relationship E = F/q. This approach effectively allows for the calculation of the electric field needed to counteract gravity and achieve levitation.
arod2812
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Homework Statement


A tiny ball (mass = 0.014 kg) carries a charge of -17 C. What is the electric field magnitude that would cause the ball to float above the ground?


Homework Equations


what equation should I use? I am not sure how to even start this problem.

The Attempt at a Solution


Would using E = q/ ((E0 * A) be a good start?
 
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Not even that complicated, there's a ball with a mass m

So there's a gravitational force acting downward on the ball that you should be able to find out

You need to counter this gravitational force with another force caused by an electric field

If you know the charge, you just need to find the electric field. What's the relationship between charge, electric field, and actual force?
 
I think I got it... So i should use the E=F/q. And the force is the mass*acceleration which is gravity because it is directed downward.

Thanks.
 
Right

so Fgrav=Felectric

and Felectric=E*q
 
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