5. Which of the following is velocity? * 2 points
A. 20 m/s
B. 40 m/s east
C. 40 m
D. 20 m

Imagine that someone pushes one marble toward a motionless marble. would there still be action-reaction forces involved in the collision? how might the marbles’ motions be changed? ?

Atwo-stage air compressor operates at steady state, compression 10m^3/min of air from 100 kpa and 300k to 1200 kpa. an intercooler between the two stages cools the air to 300k at a constant pressure of 350 kpa. the compression processes are isentropic. a) calculate the power required to run the compressor, in kw b) compare the result to the power required for isentropic compression from the same inlet state to the same final pressure.

What is the force that opposes motion and works against the downward pull? a) friction b) gravity c) weight d) acceleration