I'm studying for an exam on Saturday and some of the old practice exams don't have explanations for the solutions so I came on here for help. Thanks in advance.(adsbygoogle = window.adsbygoogle || []).push({});

1. A conducting sphere of radium 2m carries a charge of 3uC. A point charge of -2uC is 3m away from the sphere center. Find the magnitude of electric field at point P halfway between the sphere center and the point charge.

The correct answer is 0. However, I'm not too sure I understand why it's 0. Is it because the point P is inside the conducting sphere?

2. A square loop is placed in the plane of the page next to a wire with current I going into the page. If the current I increases with time, what is the direction of the force on the loop?

The correct answer is "the force is zero". However, I thought it would be up because of the right hand rule for the magnetic field of wires carrying a current.

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# Homework Help: Electric Field and Magnetic Field

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