Calculating Mars's Orbital Period Using Kepler's Third Law

[Lance WIlliam]

Homework Statement

Mars's orbit has a diameter 1.52 times that of Earth's orbit.
How long does it take Mars to orbit the Sun?
in years.

Homework Equations

I tried using T^2=4(pi)^2r^3/GM

I got 1.88years...but its wrong...

The Attempt at a Solution

 

[DaveC426913]

Homework Statement

Mars's orbit has a diameter 1.52 times that of Earth's orbit.
How long does it take Mars to orbit the Sun?
in years.

Homework Equations

I tried using T^2=4(pi)^2r^3/GM

I got 1.88years...but its wrong...

The Attempt at a Solution

What makes you think it's wrong?

Mars' year is 687 Earth days...

 

[Kurdt]

With these things it would help if you showed your work so people can see exactly where you went wrong.

I think its the radius that is 1.52 times that of Earth's not the diameter. As Dave points out, you're correct.

 

[Lance WIlliam]

Thankyou I got it..."masteringphysics" always wants answers in the craziest of ways...