Question
If you suddenly multiplied the mass of Earth by a factor of 4, how would the period of a satellite change, if the radius of its orbit did not change?
4 times as long
1/4 as long
2 times as long
1/2 as long
Unchanged
4 times as long
1/4 as long
2 times as long
1/2 as long
Unchanged
Answers
Scott
the centripetal force (gravity) is now 4 times as large
f = m v^2 / r
multiplying f by 4 (and keeping m and r constant) means that v is doubled
doubling the velocity would halve the period
f = m v^2 / r
multiplying f by 4 (and keeping m and r constant) means that v is doubled
doubling the velocity would halve the period