Which of the following is the best example of uniform circular motion? a. a child riding on a constantly spinning merry-go-round b. a car on a road curving back and forth as it passes through hills c. a pendulum bob swinging back and forth in a curved path d. a baseball that is hit up and out of the park for a home run

A. because as the merry-go-round spins the child accelerates towards the center of the merry-go-round at a uniform rate.

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