Compare the liquid pressure at the surface of a swimming pool and the bottom of the swimming pool

The pressure difference is equal to the product of density , height and g

Given that h is height difference between bottom and surface of a pool

P  

b

​  

−P  

s

​  

=dgh

Density d of water is 1

So we get P  

b

​  

−P  

s

​  

=gh

Therefore option A is correct

Explanation:

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