Please explain why this answer is correct. The plates of an isolated parallel pl
ID: 1278399 • Letter: P
Question
Please explain why this answer is correct.
The plates of an isolated parallel plate capacitor with a capacitance C carry a charge Q. The plate separation is d. Initially, the space between the plates contain only the air. Then, a Teflon (k = 2.1) sheet of thickness 0.5d is inserted between, but not touching, the plates. How does the electric field between the plates change as a result of inserting the Teflon sheet? a) The electric field will decrease to approximately one-half its initial value. b) The electric field will not be affected. c) The electric field will increase to approximately twice its initial value. d) The electric field will be zero volts per meter.Explanation / Answer
The electric field between the plates of the capacitor will be directed from positive plate to negative plate. If a dielectric material is placed between the plates of the capacitor, an electric field is formed in the dielectric due to polarization. This electric field inside the dielectric will be directed in a direction opposite to the field due to capacitor plates. Thus, the net field between the plates decreases. Therefore, the correct option is option (a).