A capacitor with capacitance 5   μ F is charged to 5   μ C . If the plates are pulled…

A capacitor with capacitance 5 μF is charged to 5 μC . If the plates are pulled apart to reduce the capacitance to 2 μF, how much work is done?
  1. 6.25×10–6 J
  2. 2.55×10–6 J
  3. 2.16×10–6 J
  4. 3.75×10–6 J

Solution

Uinitial=Q22C1
Ufinal=Q22C2
Work done =Ufinal-Uinitial
=Q22C2-Q22C1
=5×10-622×2×10-6-5×10-622×5×10-6 
=254-52×10-6
=154×10-6 =3.75×10-6 J

Asked in: JEE Main 2019 (09 Apr Shift 1)

Practice more Electrostatics questions on Aicharya