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In fig(a) electron is shot directly away...

In fig(a) electron is shot directly away from a uniformly charged plastic sheet, at speed `V_(s)` the sheet is nonconducting flat , and very vertical component versus time t until the return to the launch point. What is the sheet's surface charge density ?

Text Solution

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The correct Answer is:
`(2epsilon_(0)mv_(s))/(et_(0))`
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