Recent content by rzwhipple

Maybe I was unclear, here is what I did: \frac{1}{2}mV^{2}_{I} - \frac{GmM}{R_{I}} = \frac{1}{2}mV^{2}_{F} - \frac{GmM}{R_{F}} V^{2}_{I} - \frac{2GM}{R_{I}} = V^{2}_{F} - \frac{2GM}{R_{F}} V^{2}_{F} =V^{2}_{I} - \frac{2GM}{R_{I}} + \frac{2GM}{R_{F}} V_{F} = \sqrt{V^{2}_{I} -...

Ahh, thanks this worked nicely, I didn't use the formula for energy since you need both masses, but problem does say to neglect drag so the pot energy is the same initial and final, and mass of the object was in every term so that dropped out. Thanks again!

Homework Statement Object is moving directly toward earth initial V = 2000 m/s distance from center of Earth = 8 X 10^{7} m Determine speed at impact Homework Equations g = \frac{GM}{R^{2}} The Attempt at a Solution I am guessing I'll need to integrate to get velocity, but am not...