Question

Neglecting air resistance and the weight of the propellant, determine the work done in propelling a four-ton satellite to the following heights. a) 100 miles above Earth.b) 300 miles above Earth.

Answer 1

Explanation:

Work = force × distance

force = mass × acceleartion due to gravity

a four ton satellite will have a force of 4× 1000 ×10 = 40KN (1000Kg = 1 ton)

1 mile = 1609.34 metre

therefore (a) 100 miles above the earth

work = 40000 × 100×1609.34

= 6437360000J

=6.4GJ

(b) 300 miles above the earth

work = 40000×300×1609.34

= 1.93×10¹⁰ J