Q1. A disk with radius 0.5 m is oriented with its normal unit vector n at an angle of 30° to a uniform electric field E with magnitude 2.0 × 103 N/C.
a) What is the flux through the disk?
b) What is the flux through the disk if it is turned so that its normal is perpendicular to E?
c) What is the flux through the disk if it is normal is parallel to E?
Q2. An object is 17 mm in front of a converging lens, and the image is 3 mm behind the lens. What is the focal length of the lens? Reply In mm.