Question

word prob
Use v = - 0.0098t + c ln R, where v is the velocity of the rocket, t is firing time and c is velocity of exhaust R is ratio of the mass of the rocket filled with fuel to the mass of rocket without fuel

Find the velocity of a space craft whose booster rocket has a mass ratio of 20, an exhaust velocity of 2.7 Km/s, and a firing time of 30s. Can the space craft achieve a stable orbit 300km above earth

Answer 1

just substitute the values into the equation:
R=20
c=2.7
t=30s
and use calculator.