Q. An electron is initially at rest just outside a large copper surface that has a charge density of 1.20 x10-6 C/m2. How far has the electron moved in 1.07 x10-9 s if the field is uniform over this region? (Enter the magnitude only.)
Q. Grains of sand of mass 2.80 10-3 g each, fall from a height of 0.6 m on a sticky surface at a rate of 56 grains per second per cm2. What pressure does this shower of sand exert on the surface, assuming that air resistance can be neglected?