Question

A van de Graaff generator has a metal sphere of radius 14.2 cm. To what potential can it be charged before the electric field at its surface exceeds 2.01 x 106 N/C (which is sufficient to break down dry air and initiate a spark)?
The range of a target is found to be 20km. A shell leaves a gun with a velocity of 500ms-1. What must be the angle of elevation of the gun if the ground is leueled?
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Anonymous
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