9. A salvage boat uses its winch to pull up a sunken treasure with an upward force of 4000 N. The mass of the treasure is 200 kg and the water exerts a force of 1500 N on the treasure, resisting the force exerted by the winch . The boat is directly above the treasure. Draw a free-body diagram for the treasure , calculate the acceleration , and predict the time dependence of the motion of the treasure, initially at rest.

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day