Author Question: Two skaters, both of mass 75 kg, are initially at rest on skates on a frictionless ice pond. One ... (Read 63 times)

bclement10 · **on:** Jul 28, 2018

Two skaters, both of mass 75 kg, are initially at rest on skates on a frictionless ice pond. One skater throws a 0.3-kg ball at 10 m/s to his friend, who catches it and throws it back at 10 m/s. When the first skater has caught the returned ball, what is the velocity of each of the two skaters?
a. 0.08 m/s, moving apart
c. 0.08 m/s, moving towards each other
b. 0.04 m/s, moving apart
d. 0.04 m/s, moving towards each other

Question 2

We have an initially uncharged hollow metallic sphere with radius of 5.0 cm. I place a small object with a charge of +40 C at the center of the sphere through a hole in the surface. Find the electric field present at a point 10 cm from the sphere's center. (ke = 8.99 109 Nm2/C2)
a. 9.0 106 N/C
c. 2.3 106 N/C
b. 1.1 106 N/C
d. 36 106 N/C