Spaceflight quick check

A quick check of 3 questions. After you submit, each question shows the right answer and why.

3 of 9 questions, Advanced level. Aimed at the Advanced level, your current depth. Questions you have not answered yet come first.

Show all 9 questions

ScientistQuestion 1 of 3

Which speeds are about right for low Earth orbit and for escaping Earth altogether?

About 300,000 km/s for both

About 8 km/s to orbit and about 11 km/s to escape

About 1 km/s for both

About 11 km/s to orbit and 8 km/s to escape

ScientistQuestion 2 of 3

Using the ideal rocket equation, Δu = (effective exhaust velocity) × ln(full mass ÷ empty mass), what velocity change in km/s (one decimal place) does a rocket with an effective exhaust velocity of 3 km/s and a mass ratio of 4 achieve, ignoring drag and gravity?

Your answer

AdvancedQuestion 3 of 3

Inverting the rocket equation gives mass ratio = e raised to the power (Δu ÷ exhaust velocity). What mass ratio (one decimal place) would a single-stage rocket with an effective exhaust velocity of 3 km/s need to gain 8 km/s, ignoring drag and gravity?

Your answer