Consult concept simulation 7.1 in preparation for this problem. two friends, al and jo, have a combined mass of 132 kg. at an ice skating rink they stand close together on skates, at rest and facing each other, with a compressed spring between them. the spring is kept from pushing them apart, because they are holding each other. when they release their arms, al moves off in one direction at a speed of 1.04 m/s, while jo moves off in the opposite direction at a speed of 0.784 m/s. assuming that friction is negligible, find al's mass.

In a set amount of time, a battery supplies 25j of energy to an electric circuit that includes two different loads. one of the loads produces 10 j of heat energy during this time interval. how much heat energy is produced by the second load in this time? explain your answer

If element x has 99 protons how many electrons does it have

To understand the behavior of the electric field at the surface of a conductor, and its relationship to surface charge on the conductor. a conductor is placed in an external electrostatic field. the external field is uniform before the conductor is placed within it. the conductor is completely isolated from any source of current or charge. part a: which of the following describes the electric field inside this conductor? it is in the same direction as the original external field.it is in the opposite direction from that of the original external field.it has a direction determined entirely by the charge on its surface.it is always zero. part b: the charge density inside the conductor is: 0non-zero; but uniformnon-zero; non-uniforminfinite part c: assume that at some point just outside the surface of the conductor, the electric field has magnitude e and is directed toward the surface of the conductor. what is the charge density η on the surface of the conductor at that point? express your answer in terms of e and ϵ0