Question

A 10,000kg spacecraft is traveling through space with a speed of 1200 m/s relative to Earth. A thruster fires for 2.0 min, exerting a continuous force of 25 kN on the spacecraft in a direction opposite the spacecraft’s motion. Calculate the initial momentum and the final momentum of the spacecraft.

Answer 1

Step-by-step explanation:

We are given information:

If we apply Newton's second law we can calculate acceleration:

F = m * a

a = F / m

a = 25000 / 10000

a = 2.5 m/s^2

Now we can use this information to calculate change of speed.

a = v / t

v = a * t

v = 2.5 * 120

v = 300 m/s

Force is being applied in direction that is opposite to a direction in which space craft is moving. This means that final speed will be reduced.

v = 1200 - 300

v = 900 m/s

Formula for momentum is:

p = m * v

Initial momentum:

p = 10000 * 1200

p = 12 000 000

p = 12 *10^6 kg*m/s

Final momentum:

p = 10000 * 900

p = 9 000 000

p = 9 *10^6 kg*m/s