Athin ball shell is shaped like a hollow ball with a radius of 42.8 cm. the material is a conductor with charge 0.8 nc a point charge of -5.4 nc is placed in the center of the ball. how many n / c is the electric field just outside the ball? remember positive is outwards i did this: got total charge qencloced = -4.6*10^-9 c found the field e=(qencloced/epsilon) divided by 4*pi*speed squared got 225.80 n/c. the answer in my (really annoying online test) is 265 n/c

You have two photos of a person walking. one shows the person at the corner of third and main streets, the other shows the person at the corner of tenth and main streets. there are lampposts at every corner in this town, and the first picture shows it to be 10: 32: 00 exactly. the second picture shows it to be 10: 49: 30. you know three facts: (1) all of the clocks are synchronized; (2) there are exactly 12 equal-sized blocks per kilometer in this town; and (3) the streets that cross main in this area are numbered consecutively, with no interruptions. what is the person’s average speed in kilometers per hour?