The ima of a lever can be increased by decreasing the length between the applied effort and the pivot.

Explanation:

The ideal mechanical advantage of a lever is defined as the ratio of applied resistance force to the applied effort force. It can be also defined as the ratio of effort arm to the load arm. It is given by :

= effort arm

= load arm

If the length between the applied effort and the pivot is decreased, the IMA of a lever will decreased. This is due to the direct relation between IMA and effort arm. So, the given statement is false.

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