A rocket with a mass of 2.0 × 10⁶ kg is designed to take off from the surface of the earth by burning fuel and ejecting it with an exhaust speed of 3500 m/s. What is the minimum rate at which the fuel should be consumed in order to attain liftoff? A)5.6 × 10³ kg/s B)1.4 × 10³ kg/s C)1.8 × 10³ kg/s D)2.8 × 10³ kg/s E)18 × 10³ kg/s

Question

Quizplus · Accepted Answer

The thrust must equal the gravitational force for liftoff. Thrust = exhaust speed × fuel consumption rate. Gravitational force = mass × gravity. Solving 3500 × rate = 2.0 × 10^6 × 9.8 gives rate = 5.6 × 10^3 kg/s.

A Rocket with a Mass of 2