Author Question: An astronaut is piloting a spacecraft, which is in a circular orbit around Earth. A space station is ... (Read 137 times)

ishan · **on:** Jul 29, 2018

An astronaut is piloting a spacecraft, which is in a circular orbit around Earth. A space station is ahead, on the same circular orbit. If he fires his rockets briefly to decrease the forward speed of the rocket, what will happen?

What will be an ideal response?

Question 2

As a spaceship is moving toward Earth, an Earthling measures its length to be 325 m, while the captain on board radios that her spaceship's length is 1150 m.

(c = 3.00 108 m/s)
(a) How fast is the rocket moving relative to Earth?
(b) What is the TOTAL energy of a 75.0-kg crewman as measured by (i) the captain in the rocket and (ii) the Earthling?

Yixagurpuldink · **Reply #1 on:** Jul 29, 2018

Answer to Question 1

The spacecraft will be put into an elliptical orbit with an apogee equal to the original radius. The average radius of this orbit is smaller, so it will take less time to complete one revolution. So if the speed increment is calculated correctly, when he completes one revolution, bringing him back to the original radius, he could be caught up with the station. At that point, a forward burst could put him in the same circular orbit as the station.

Answer to Question 2

(a) 0.959c = 2.88 108 m/s
(b) (i) 6.75 1018 J (ii) 2.39 1019 J