Question

You charge a capacitor and then remove it from the battery. The capacitor consists
of large movable plates with air between them. You pull the plates a bit farther
apart. Describe whether the following quantities increase, decrease or stay the
same: Q, C, E, DVc, U. Compare this to what would happen if you moved the plates
farther apart while still hooked up to the battery.
(ch.24 physics2)

Answer 1

Wilhen we charge capacitor and then remove it from charging batterey then charge reamains constant. " New charge d'=go Cinitial charge) i charge, & remains same. Now, we know that capacitance (ch of a Barallel Blate capacitor given by a God where, & permitivity of free space A7 Area i cat plates " if we move Plates apart from each other capacitance blate distance between the d > a show, ole creases . capacitance, a decreases. potential difference between the plates veg a is constant and a decreases a V Mureases Now, Electric field , & I , Here, V and to d both are increasing in same manner. Therefore E remains constant Now, Energy Store, U= \scr?ch v BA 0) - the one 12 . Vad, therefore increases.

If the capacitor is still hooked up to to the battery then potential difference remains constanta . V remains constant. Now, c = COA and d is increasing Now e decreases Here. V is Now, constant and d is increasing &= v and &ald £ decreases Now, charge, s= cv = GAxv Here, Go A and r are constant. nga i d is increasing .. & decreases. Now Energy stored U= clo : v is constant and c ed, U=2012 is decreasing . U o also decreases