In fair weather, over flat ground, there may be a downward electric field of 155
ID: 2223060 • Letter: I
Question
In fair weather, over flat ground, there may be a downward electric field of 155 N/C. (a) Assume that the Earth is a conducting sphere with charge on its surface. If the electric field just outside is 155 N/C pointing radially inward, calculate the total charge on the Earth and the charge per unit area. _______ C _______ nC/m2 (b) At an altitude of 220 m above the Earth's surface, the field is only 125 N/C. Calculate the charge density of the air (assumed constant). [Hint: See the Conceptual Example within the chapter that discusses "Field Lines for a Thin Spherical Shell".] _______ C/m3Explanation / Answer
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