D. 100 kilometers cuz the more kilometers the better the altitude!!!
<span>We know , E = kQ/r^2 where q = charge and r is separation between point and point charge.
Now, At P, E= kQ/r^2
Since, Q can't be changed, we can do that by varying r
2E = 2kq/r^2
2E = kq/ (r/ sqrt2)^2
Hence, if we bring Q closer such that distance between P and Q becomes r/ sqrt 2, E will get doubled.</span>
Answer:
Y
Explanation:
Y will produce the strongest magnetic force because the current intensity is medium and it has 50 turns in the wire. the number of turns will increase the force because the magnetic field will be more concentrated.
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