Physics Help?

Question

An airline executive decides to economize by reducing the amount of fuel, required for long distance flights. He orders the ground crew to remove the paint from the outer surface of each plane. The paint removed from a single plane has a mass of approximately 100 kg.

(a) If the airplane cruises at an altitude of 24,000 m, how much energy is saved in not having to lift the paint to that altitude?

________MJ

(b) How much energy is saved by not having to move that amount of paint from rest to a cruising speed of 230 m/s?

_________MJ

Answer 1

(a) Potential energy = m*g*h (mass x height x gravitational constant), if you don't take the effect of height on gravitation in account

Result = 23.544 MJ (or 24 MJ if you calculate with g = 10)

(b) Kinetic energy = m*v2/2 (mass x square of velocity / 2)

Result = 2.645 MJ (if you don't take friction into account)

Answer 2

Potential Energy  = 1/2 (mass ) *(hight)

Kinetic Energy      = 1/2 (Mass)*  (Velocity) ^2

Answer 3

a. Not enough

b. a little