Stupid physics problem.

[UsmanB]

i did a quick search of ur problem on google and found this problem on a forum:

A window washer pulls herself upward using the bucket-pulley apparatus show in Fig. 4-42 (the woman is in a bucket, a rope tied to the top of the bucket, and she's pulling on the downward direction of rope that goes up over the pulley) (a) How hard must she pull downward to raise herself slowy at a constant speed? (b) If she increases this force by 10 percent, what will her acceleration be? The mass of the person plus the bucket is 65 kg.

This was the reply from a member.

Find the accelerations of all four parts. (g=10)

a = [(m2-m1)/(m1+m2)]g

a1 = [(180kg - 120kg)/(180kg + 120kg)]10m/s^2
a1 = 2m/s^2

a2 = [(120kg - 80kg)/(120kg + 80kg)]10m/s^2
a2 = 2m/s^2

a3 = [(80kg - 40kg)/(80kg + 40kg)]10m/s^2
a3 = 3.33m/s^2

a4 = [(40kg - 0kg)/(40kg + 0kg)]10m/s^2
a4 = 10m/s^2


Find the time in seconds.

s = .5at^2

16m = .5 (2m/s^2) t^2
t^2 = 16m
t1 = 4s

t2 = 4s (same acceleration)

16 = .5 (3.33m/s^2) t^2
t3 = 3.1s

16 = .5 (10m/s^2) t^2
16 = 5t^2
t^2 = 3.2
t4 = 1.8s

Adding the times of 4+4+3.1+1.8 = 12.9 seconds.

And for your other problem i found this on google. http://faculty.salisbury.edu/~jwhowa...l/lecture4.htm

that is the exact way to do ur problem, scroll down and u'll find a problem that reads "An 18.0 kg box is released on a 37.0° incline and accelerates down the incline at 0.270 m/s2. Find the coefficient of friction and the frictional force." and they have a picture and show u how to solve it good luck and im sure that if u looked in the chapter ur doing right now u could find perhaps an example, i know the physics book i have right now doesnt have each example for each type of problem so u have to play with equations given.