Two students both kick a soccer ball. Havanna's ball travels three times as fast as Mitzi's ball. How does the kinetic energy of the two soccer balls compare? A. Both soccer balls have the same amount of kinetic energy, because they have the same mass. B. Mitzi's soccer ball has 3 times as much kinetic energy, because it travels a third of the speed. C. Havanna's soccer ball has 9 times the kinetic energy, because it travels at 3 times the speed. D. Havanna's soccer ball has 3 times because it travels at 3 times the speed.

Given the position vector of the particle r(t)=(t+1)i+(t^2−1)j+2t k, find the particle's velocity and acceleration vectors at t=1

The average density of the planet uranus is 1.27 103 kg/m3. the ratio of the mass of neptune to that of uranus is 1.19. the ratio of the radius of neptune to that of uranus is 0.969. find the average density of neptune.

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