Crazy Ellie is piloting the Virgin Galactic Space Plane
as it coasts from Earth to Mars.
The initial velocity of the M = 26 tonne craft is
v0 = 15 km/s,
directly toward Mars.
The ship is exactly on schedule to reach
its destination at 2:00 PM tomorrow,
in exactly 10 hours.
Exhausted by last night's party, Ellie falls
asleep. Her elbow pushes the thrust-control
button, causing the engines to push the ship
back toward Earth with a
constant force of 500 kiloNewtons.
Two minutes later, she jerks awake and
sits up, turning the engines off.
- What is the velocity of the ship now?
- How many miles behind schedule is the ship now?
- If the ship continues to travel toward Mars
with its current velocity, when will it arrive
at the destination?
The answers (PDF)