4. A rocket entering Mars' atmosphere can accelerate at -20.0 m/s2. If the rocket is originally going 1600 m/s and has 10 seconds to reach its cruising velocity, what will that final velocity be?

v = 1400 m/s

Explanation:

Acceleration of the rocket, a = -20 m/s²

Initial speed of the rocket, u = 1600 m/s

Time, t = 10 s

We need to find the final velocity of the rocket. We can use first equation of motion to find it.

v = u+at

Put all the values,

v = 1600+(-20) (10)

= 1600-200

= 1400 m/s

So, the final velocity of the rocket is 1400 m/s.