Simulation: http://phet.colorado.edu/sims/lunar-lander/lunar-lander_en.html In t
ID: 1411592 • Letter: S
Question
Simulation: http://phet.colorado.edu/sims/lunar-lander/lunar-lander_en.html
In the following simulation, please help me determine which is the thrust and velocity vectors, and how to determine that?
"The thrust vector is yellow, while the velocity vector is green. We are able to know this because the velocity vector points to the direction that the lander is moving. The thrust vector points to the same direction as the velocity vector as it speeds up over time, and points to the opposite direction from the velocity vector as it slows down over time. Also, the yellow vector is more predominant when thrusting, while the green vector is more predominant when the thrust is off."
Would my answer be correct?
Thank you!
Explanation / Answer
The yellow vector indicates net acceleation and green vector indicates the velocity. The yellow vector gives the net force acting on the it, which means sum of all forces acting on it. As the thrust increases instead of moving down it is moving up. In this case the thrust is more than the weight. Hence, it moves upwards. Incase if the thrust is less than weight, it moves downwards. The velocity vector is positive when moves upwards and negative when it moves downwards. In the absence of thrust it is under free fall.