- #1

- 326

- 3

## Homework Statement

The binary star system Krell consists of two stars, Krell A and Krell B, orbiting each other, with no other ojects nearby. Assume Krell A, the smaller star of mass mA, moves in a circle of radius rA at speed vA. Krell B, the larger star of mass mB = 2.51mA), moves in a circle of radius rB at speed vB. The two stars are separated by a distance d.

Find the ratio of the periods of orbit TA/TB

## Homework Equations

I would assume these formulas:

→T²/r³

→T²/r³ = 4π²/(G(M + m))

## The Attempt at a Solution

I believe the approach is...

T_A²/R_A³ = T_B²/R_B³

T_A²/T_B² = R_A³/R_B³

(T_A/T_B) = √((R_A/R_B)³)

From the previous part of the problem, I've found that R_A/R_B = 2.51. Then, I substitute that for the above expression and got the answer incorrect.

T_A/T_B = √(2.51³) ≈ 3.98

But the answer is incorrect.