Circular Motion and Universal Law of Gravitation Solutions Check Requested

AI Thread Summary
The discussion revolves around calculating the surface acceleration due to gravity on a white dwarf star, which has the mass of the Sun and the radius of the Moon. The user attempted to solve the problem using the Universal Law of Gravitation but was unsure about the setup and the meaning of "F" in the equation. They substituted the gravitational constant and simplified the equation, ultimately arriving at a value of 4.38x10^7 m/s^2. The response confirmed that the user's approach was on the right track, clarifying that the acceleration can be calculated using the formula a = G * (M/R^2). The conversation emphasizes the importance of correctly applying gravitational principles to determine acceleration.
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Homework Statement



1. A typical white dwarf star, which once was an average star like our Sun but now in the last stage of its evolution, is the size of our Moon but has the mass of our Sun. What is the surface acceleration due to gravity on this star? (Msun = 1.99 x 10^30 kg, Rmoon = 1.74 x 10^6 m)

- R = radius and M = mass (in reference to Msun and Rmoon)

Homework Equations



Universal Law of Gravitation
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The Attempt at a Solution



I don't know how to start, but still gave it a try.
First of all, I didn't know what the "F" on the other side of the equation is supposed to be or set the equation up to find the acceleration.
I started by substituting G for 6.67426x10^-11 and got rid of the 2nd mass altogether.
I plugged in the mass of the sun, 1.99x10^30 kg divided by the radius of the moon, 1.74x10^6 m.
Thus I ended up with 4.38x10^7 m/s^2.

Is this the solution?
 
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Your try was a good one, well figured out.

We have F = m_2 a = G \frac{m_1 m_2}{r^2},
so a = G \frac{m_1}{r^2}.
 
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