What are the strength and direction of an electric field that will balance the weight of a proton?

Question

anonymous · Answer

You need more information to make the question clear. Is this an electric field to make the proton "hover" in the air, when it would otherwise fall due to gravity?

We do know the charge of a proton is positive. And the mass is 1.67e-27kg. Intuitively, the e-field would have to be repulsive (positive) from the bottom or attractive (negative) from the top to draw the proton "up" against gravity. The strength of this e-field has to equal the pull from gravity mg.

anonymous · Answer

Sorry, I copied the problem straight from the textbook. whats the major difference in solving?

anonymous · Answer

I got 1.03 which close enough, so how do i find the direction?