Newton: Motion and Force - Please help me!?

Question

1. What average force is need to accelerate a 7.0g pellet from rest to 500m/s over a distance of 0.700 m along the barrel of a rifle?

2. A window washer pulls herself upward using the bucket-pulley appartus (shown in a pic). (a) How hard mush she pull downward to raise herself slowly at a constant speed? (b) If she increases this force by 10%, what will her acceleration be? The mass of the person plus the bucket is 75kg.

Please explain and show me how to do this so that I can have a better understanding of this topic.

Answer 1

1. V^2 = Vo^2 + 2*a*d where V = final velocity, Vo = original velocity = 0, d = barrel length. Solve for a

F = m*a where m = bullet mass and a is from above.

2a. In that pic, is there a pulley at both top and bucket? How many times does the rope go from pulley to bucket? If top only, and 2 times: She has to pull her own weight plus the bucket.
W = m*g where m = her own mass plus the bucket's and g = 9.8 m/s^2.
2b. Figure 10% for the force from 2a and plug into F = m*a.