A 74.0kN kN spaceship comes in for a vertical landing. From an initial speed of 1.00 km/s {\rm km/s}, it comes to rest in 2.40min min with uniform acceleration.

Question

What braking force must its rockets provide? Ignore air resistance.

Answer 1

-1km/s / (2.4min * 60s/min)
= -1km/s / 144s
= -1/144 km/s^2 * 1000m/km
= -6.94 m/s^2

Answer 2

f=1.26x10^5 N