handout answers

1. a = 3.33 m/s^2 DOWN for the 8 kg block.
2.
a) upwards
c) T = 5000 N
d) M = 625 kg

3.
b) T = 1050 N
c) If up is positive, the acceleration of the helicopter is +5.2 m/s^2, and the package is -9.8 m/s^2. (Many of you had this sign wrong when we were working on it on Friday! Your other work should be correct.)
delta_x for the helicopter = 70.4 m
delta_x for the package = 40.4 m
distance = 70.4 m + 5 m - 40.4 m = 35.0 m

4. a = 0.75 g
5.
a) a = F/6m
b) left tension = F/2, right tension = 5F/6

6.
b) F = mu*mg/(cos(theta) - mu*sin(theta))

7.
a) a = 3.0 m/s^2
c) a = 1.96 m/s^2 (NOT the same as part a!)

8. F = g(m1 + m2)/mu