Compute all parts of given question:
Question: A parallel plate capacitor with plates of area 500 cm2 is charged to a potential difference V and is then disconnected from the voltage source. When the plates are moved 0.4 cm further apart, the voltage between the plates increases by 100V.
Part A: What is the charge Q on the positive plate of the capacitor?
Part B: How much does the energy of the capacitor change due to the movement of the plates?
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