1          If two particles have equal kinetic energies, are their momenta necessarily equal? Explain.                                                                                                                                               

2          Where is the center of mass of Earth's atmosphere?                                              

3          An airplane propeller is rotating at 1900 rev/min.Compute the propeller's angular velocity in rad/s.                                                                                                                    

4          Two ice dancers are at rest on the ice, facing each other with their hands together. They push off on each other in order to set each other in motion. The subsequent momentum change (magnitude only) of the two skaters will be ____. Also write it’s (the answer you choose) detail reason.                                                                                              

A. greatest for the skater who is pushed upon with the greatest force

B. greatest for the skater who pushes with the greatest force

C. the same for each skater

D. greatest for the skater with the most mass

E. greatest for the skater with the least mass                

5          How much work is done by an applied force to lift a 20-Newton block 2.0 meters vertically at a constant speed?                                                                                 

Q         A student with a mass of 50.0 kg runs up three flights of stairs in 10.0 sec. The student has gone a vertical distance of 8.0 m. Determine the amount of work done by the student to elevate his body to this height. Assume that her speed is constant.