A. A distant star has a single planet circling it in a circular orbit of radius

Question

A. A distant star has a single planet circling it in a circular orbit of radius 6.5 × 10^11 m. The period of the planet’s motion about the star is 846 days. What is the mass of the star? The value of the universal gravitational constantis 6.67259 × 10^11 N · m^2/kg^2.
Answer in units of kg.

B. The sketch shows a conical pendulum. The ball swings in a circular path because of the string attached at the top. The tension T in the string and weight W of the ball are shown by vectors. A parallelogram created with these vectors shows that their resultant F lies in the plane of the circle.

1. centripetal force
2. centrifugal force
3. frictional force
4. angular force

Please don't copy and paste from Google. I've already referred to Google and haven't been able to find any assistance. Please show your work and I will GLADLY rate you A+!

Explanation / Answer

Part A)

Kepler's Third Law is the formula to use here. That formula is

T2 = (42/GM)r3

T is the period, and it must be in seconds. We are given 846 days. With 24 hours in a day and 3600 seconds in an hour, that is 7.31 X 107 sec

Solve for M

M = 42r3/GT2

M = (42)(6.5 X 1011)3/(6.67259 X 10-11)(7.31 X 107)2

M = 3.04 X 1031 kg

Part B)

The definition of Centripetal Force is ...

Any force, acting toward the center of a circle, that keeps an object in the circular path. Therefore, you can see that the resultant force is pointing directly to the center of the circular path. The only possible choice is that it is a Centripetal Force.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.