Author Question: A rock is moving with speed v. If the mass of the rock were tripled and the speed were reduced to ... (Read 78 times)

renzo156 · **on:** Jul 28, 2018

A rock is moving with speed v. If the mass of the rock were tripled and the speed were reduced to v/3, which of the following statements would be true?
a. The kinetic energy of the rock is smaller than in the first case, but the momentum is larger.
b. The kinetic energy of the rock is smaller than in the first case, but the momenta of both are the same.
c. The kinetic energies of the rocks are the same in both cases.
d. The kinetic energy of the rock is 1/9 its previous value.

Question 2

An electron with a charge value of 1.6 10-19 C is moving in the presence of an electric field of 300 N/C. What force does the electron experience?
a. 2.3 10-22 N
c. 6.4 10-17 N
b. 4.8 10-17 N
d. 1.9 10-21 N