A pressure sensor uses a parallel-plate capacitor consisting of two square metal plates of side length w w\,w separated by an air gap of distance ggg. This arrangement has a capacitance CCC.
A modified version of the sensor is designed with square plates of side length 2.5w 2.5w\,2.5w and a gap distance of 1.5g. Additionally, the air gap is filled with a flexible polymer dielectric of relative permittivity εr=1.2\varepsilon_r = 1.2εr=1.2.
What is the capacitance of the modified sensor in terms of CCC?
2.0C2.0 C2.0C
4.2C4.2 C4.2C
5.0C5.0 C5.0C
7.5C7.5 C7.5C
63 exam-style questions on AQA A Level Physics Capacitance (A-level only), covering Capacitance (A-level only), Parallel plate capacitor (A-level only), Energy stored by a capacitor (A-level only), and Capacitor charge and discharge (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.