Understanding Electric Fields: Measuring the Electric Field at a Point P

AI Thread Summary
To measure the electric field at point P near a negatively charged metallic ball, a positive charge q is placed at that point, and the force F on q is measured. The electric field E at point P is determined by the formula E = F/q, but since the electric field due to the negatively charged ball points towards it, the effective electric field is negative. Therefore, the relationship shows that E is less than F/q, leading to the conclusion that the electric field at point P is <F/q. This understanding is crucial for correctly interpreting electric fields generated by different types of charges.
shashankdubey
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Homework Statement


A negatively charged metallic ball is supported on an insulating stand.We wish to measure the electric field at a point P in the same horizontal level as that of the metallic ball.To do so,we put a positive charge q and measure F/q.The electric field at the point P is
a)=F/q
b)<F/q
c)>F/q

the answer given is <F/q...i can't understand how..


Homework Equations





The Attempt at a Solution

 
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The electric field of a point charge or a charged ball is considered positive if it points away from the charge. The electric field around a negative charge is negative. If F is the magnitude of force than E=-F/q.

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