A parallel–plate capacitor is initially charged by connecting it to a battery. The battery is then disconnected. If the distance between the plates is increased, what happens to the charge on the capacitor and the voltage across it? a. The charge remains fixed and the voltage decreases.
b. The charge decreases and the voltage remains fixed.
c. The charge remains fixed and the voltage increases.
d. The charge decreases and the voltage increases.

t the battery of potential difference  V be used to charge the capacitor of capacitance  C.

∴ the charge stored in the capacitor      q=CV

Now the battery is disconnected, so the the charge  of the capacitor becomes constant

i.e    q=constant     OR     CV=constant                (1)

Capacitance of parallel plate capacitor        C=  

d

Aϵ  

o

So if the distance between the plates is increased, then the capacitance will decrease which is compensated by the increase  in voltage across the capacitor according to equation (1).

Also the energy stored in the capacitor          E=  

2C

q  

2

⟹E∝  

C

1

                (∵q=constant)

Thus energy will increase due to the decrease in capacitance.

Explanation:

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.