A 2200-kg auto moving northward at 12.0 m/s runs into a 3800-kg ...

[Chloeellawright]

A 2200-kg auto moving northward at 12.0 m/s runs into a 3800-kg truck which is also moving northward, but at 5.00 m/s.
 
  If the vehicles lock bumpers, how fast are they moving just after the collision?

Question 2

What is the meaning of the term critical mass in regard to nuclear fission?
 
  A) This is the mass of the critical elements in a reactor, i.e., the uranium or plutonium.
  B) This is the amount of mass needed to make a power reactor economically feasible.
  C) This is the amount of material that is just on the verge of becoming radioactive.
  D) This is the minimum amount of fissionable material required to sustain a chain reaction.

[kescobar@64]

Answer to Question 1

7.57 m/s

Answer to Question 2

D