Answer:
2.5
Explanation:
The capacitance of a parallel-plate capacitor filled with dielectric is given by
[tex]C=kC_0[/tex]
where
k is the dielectric constant
[tex]C_0[/tex] is the capacitance of the capacitor without dielectric
In this problem,
[tex]C_0=1.2 nF[/tex] is the capacitance of the capacitor in air
[tex]C=3.0 nF[/tex] is the capacitance with the dielectric inserted
Solving the equation for k, we find
[tex]k=\frac{C}{C_0}=\frac{3.0 nF}{1.2 nF}=2.5[/tex]
