A positive charge Q = 1400.00 C is uniformly distributed over the volume of a sphere of radius R = 10.00 m. Suppose a spherical cavity of radius R/2 is cut out of the solid sphere, the center of the cavity being a distance R/2 from the center of the original solid sphere (see figure). The cut-out material and its charge are discarded. What is the magnitude of the electric field produced by this new charge distribution at point P, a distance r = 24.50 m from the center of the original sphere?(adsbygoogle = window.adsbygoogle || []).push({});

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I have calculated the E-field of the point using the equation E=kQ/r^2. I first did this using the radius 24.5m. I then used the radius 24.5m-5m=19.5m. I then subtracted these two E-field calculations and get the wrong answer. E(r) - E(r-R/2)

What am I doing wrong?

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# Homework Help: Spherical Cavity

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