Student Name. 9. shown below are two charged particles that are fixed in place.
ID: 2284251 • Letter: S
Question
Student Name. 9. shown below are two charged particles that are fixed in place. The magnitude of the charge Qis greater than the magnitude of the charge q. A third charge is now placed at one of the points A E. The net force on this charge due to q and Q is zero. A. Both q and Q are positive. At which point A-Eis it possible that the third charge was placed? B. Charge q is positive and charge Q is negative. At which point A-E is it possible that the third charge wa placed? c. Charge q is negative and charge a is positive. At which point A-Eis it possible that the third charge w placed? D. Both q and Q are negative. At which point A-E is it possible that the third charge was placed?Explanation / Answer
In all the cases the magnitude of q is less than Q. Electrostatic force is inversely proportional to the square of distance. So for the force of q and Q to be balanced the new charge should always be closer to q than Q in ALL THE CASES which rules out options C,D and E in all four parts.
A) Since both the charges q and Q are positive, both will either push or pull the third charge towards itself. So the new charge should be between q and Q which leaves us with option B only.
B) Since q and Q have opposite signs, one will push and the other will pull the third charge. So clearly the two charges sholud be on the same side of the third charge leaving us with option B
C) same reason as option B
D) same reason as option A