How to find the mass of a planet when given the radius?

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To determine the mass of a planet using its radius, first calculate the gravitational acceleration at the planet's surface. This can be done by measuring the time it takes for an object to fall a known distance, using the meterstick and stopwatch. Once the gravitational acceleration is found, apply the formula F=G*m1*m2/R^2, where G is the gravitational constant, m1 is the mass of the planet, and R is its radius. Rearranging this formula allows for the calculation of the planet's mass. Understanding these steps is crucial for solving the problem effectively.
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1. So for homework my teacher gave us this question (and this is quoted from his worksheet):
You graduate college with a degree in astrophysics and are assigned as an astronaut to explore a distant planet for NASA. You land on this planet and are told to determine the mass of the planet there. You have a meterstick and a stopwatch. Observations from space tell you the radius of the planet that you land on. How do you go about measuring the mass of this planet?

2.F=G*m1*m2/R^2

How do I even begin to complete this problem? Do I have to find the acceleration of gravity on the planet? Any help is appreciated.
 
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CluelessPhysics said:
1. So for homework my teacher gave us this question (and this is quoted from his worksheet):
You graduate college with a degree in astrophysics and are assigned as an astronaut to explore a distant planet for NASA. You land on this planet and are told to determine the mass of the planet there. You have a meterstick and a stopwatch. Observations from space tell you the radius of the planet that you land on. How do you go about measuring the mass of this planet?

2.F=G*m1*m2/R^2

How do I even begin to complete this problem? Do I have to find the acceleration of gravity on the planet? Any help is appreciated.

Yes, you have to find the gravitational acceleration on the surface of the planet.
 

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