Two baseballs are thrown vertically up from the ground at the same speed, one on Earth, and one on Mars. The baseball on Earth reaches a maximum height of 50 m. Which ball hits the ground first and by what time difference? (gMars = 0.38 gEarth) a) Mars by 7.4 s
b) Earth by 7.4 s
c) Earth by 9.7 s
d) Mars by 3.7 s
e) Earth by 10.4 s

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

k2s for potassium sulphide