Final answer:
To calculate the charge on the plates of the parallel-plate capacitor, use the formula Q = CV, where Q is the charge, C is the capacitance, and V is the potential difference. The electric field can be calculated using Gauss's law, and when the Teflon is removed, the electric field is zero.
Step-by-step explanation:
To calculate the charge on the plates of the parallel-plate capacitor when they are charged to a potential difference of 10.0 V, we can use the formula Q = CV, where Q is the charge, C is the capacitance, and V is the potential difference. The capacitance of a parallel-plate capacitor is given by C = εA/d, where ε is the permittivity of the dielectric material, A is the area of the plates, and d is the separation between the plates. In this case, the capacitance can be calculated as C = (ε0εrA)/d, where ε0 is the permittivity of free space (8.85 x 10^-12 F/m), εr is the relative permittivity of Teflon (2.1), A is the given area (2.90 x 10^-2 m^2), and d is the given separation (1.60 mm).
Using these values, we can calculate the capacitance. The charge on the plates can then be found by multiplying the capacitance by the potential difference.
To calculate the electric field inside the Teflon using Gauss's law, we can use the formula E = σ/εrε0, where σ is the surface charge density, εr is the relative permittivity of Teflon, and ε0 is the permittivity of free space. The surface charge density can be found by dividing the charge on the plates by the area of the plates.
When the Teflon is removed and the voltage source is disconnected, there is no charge on the plates. Therefore, the electric field is zero in this case.