a)Point charge Q = +7.25 μC is fixed at the origin. Point charge q = +1.60 μC is now carefully placed on the positive y-axis, and it floats at (0,7.88). Find the mass of q.(adsbygoogle = window.adsbygoogle || []).push({});

b) Refer to question a. Suppose that, as charge q is floating, the point charge Q at the origin begins to lose its charge at a constant rate of dQ/dt = -0.285 μC/s. Find the speed with which point charge q is approaching the origin when it is at (0, 3.94).

I got the answer a by using F = k x (q1 x q2 / r^2) and F = mg ---> m = 1.71 kg

I am completely stuck on b. Can someone please help??

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# Homework Help: Speed at Which Point Charge in Approaching origin / loss of charge at constant rate

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