1. A single capacitor of capacitance C is connected to a battery of voltage E. Then the battery is disconnected and the polarity of the battery is reversed, find work done by batt.
2. A soap bubble is given a charge -q.
its radius
a.increases
b.decreases
c. no change
d. it will change but info is insufficient to find whether it will increase/decrease
ans for the second one is d.
plz solve both the Qs ith explanations
1ANS TO 1
initial charges will be q and -q say on 1st and 2nd plate of the parallel plate capacitor
when the polarity is reversed the chrges will become -q and q on 1st and 2nd respectively
so charge transferred by the battery is 2q and through the potential E so work done is 2qE
1the Q (which is given in book) asks only of the magnitude
But ideally work done BY battery should be negative.
1if we consider the first configuration then the work would be neg
if we consider the second one then the work would be positive
do you mean to say that the first configuration prevails
i may be wrong
1sorry , I can;t tell u for sure. Hvent got a hang of this topic yet. [2][7]
1the same is with me too i know capacitance but not to the extent to answer each and every question which rises in my mind[2][7]