If the central mass M increases while the orbit radius r remains fixed, what happens to the orbital velocity v?

Unlock all questions

This demo includes only 20 questions. Upgrade to access hundreds of questions, flashcards, exam simulations, and disable ads.

Full question bankExam simulationsFlashcards
From $24.99Unlock all

Study for the Praxis Physics Exam with interactive questions and detailed explanations to enhance your understanding of physics concepts. Prepare for your exam efficiently!

Multiple Choice

If the central mass M increases while the orbit radius r remains fixed, what happens to the orbital velocity v?

Explanation:
For a circular orbit the speed is set by balancing gravity with the needed centripetal acceleration. This gives v^2 / r = GM / r^2, so v^2 = GM / r and v = sqrt(GM / r). With the orbit radius fixed, v is proportional to the square root of the central mass M. Increasing M strengthens gravity, so the object must move faster to stay in orbit. Therefore the orbital velocity increases (the magnitude of velocity, which is positive; the direction stays tangential).

For a circular orbit the speed is set by balancing gravity with the needed centripetal acceleration. This gives v^2 / r = GM / r^2, so v^2 = GM / r and v = sqrt(GM / r). With the orbit radius fixed, v is proportional to the square root of the central mass M. Increasing M strengthens gravity, so the object must move faster to stay in orbit. Therefore the orbital velocity increases (the magnitude of velocity, which is positive; the direction stays tangential).

More Multiple Choice Questions
Subscribe

Get the latest from Passetra

You can unsubscribe at any time. Read our privacy policy