Compare the kinetic energy of a 21,000 kg truck moving at 130 km/h with that of an 84.0 kg astronaut in orbit moving at 28,000 km/h.

K.E of the Astronaut is greater

Explanation:

Mathematically;

K.E = 1/2 * m * v^2

For the truck, the kinetic energy will be

1/2 * 21,000 * 130^2 = 177,450,000 J

while for the astronaut, his K.E will be

1/2 * 84 * 28,000^2 = 3.2928 * 10^10

This shows that the K.E of the astronaut is greater

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