Newton HW

1.  Consider a 0.05 kg model rocket.

a.  If it has an engine attached that provides 6-N of thrust, what is the rocket's acceleration?
b.  If the thrust time is 0.5 seconds, what is the final "burn out" velocity?
c.  What will happen after "burn out"?

2.  These questions are about mass and weight (the force due to gravity)?

a.  What exactly is the difference between mass and weight?
b.  What is the weight of a 65 kg woman?
c.  How do weight and mass change/compare on the Moon?

3.  Imagine standing on a scale in an elevator.

a.  How would the scale reading change if you were moving UP with a constant velocity?
b.  How would the scale reading change if you were moving DOWN with a constant velocity?
c.  How would the scale reading change if you were accelerating up with a constant acceleration?
d.  How would the scale reading change if you were accelerating down with a constant acceleration?
e.  You have a mass of 80 kg.  If were in a moving elevator, accelerating UP at 1 m/s ^2, what would the scale read?
f.  What would the scale read if you were in a freely-falling elevator?

4.  Give an example of Newton's 3rd law in action.

5.  Why do all objects fall toward the Earth with the same acceleration (in the absence of air resistance)?  Answer this question in light of Newton's 2nd law.