In space of horizontal `EF (E = (mg)//q)` exist as shown in figure and a mass m is released at the end of a light rod. If mass m is releases from the position shown in figure find the angular velocity of the rod when it passes through the bottom most position
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Answer

B

Explanation

By work energy throrem `W_(g)+W_("elec")=DeltaKE`

`mgl(1-1/sqrt(2))+qExxl/sqrt(2)=1/2 mv^(2)-0`
`( :' E=(mg)/q) u=sqrt(2gl), W=u/l=sqrt((2g)/l)`