Q: A NASA satellite has just observed an asteroid that is on a collision course with the Earth. The asteroid has an estimated mass, based on its size, of 4.85×10^9 kg. It is approaching the Earth on a head-on course with a velocity of 593 m/s relative to the Earth and is now 4.85×10^6 km away. With what speed will it hit the Earth's surface, neglecting friction with the atmosphere? I found g using (mass of earth)(mass of sat)/(r^2) of course since x = 4.85×10^6 km = 4.85×10^9 m so g= (5.98e24)/(4.85e9) <--since one of the r's cancels out with the mass of sat then i used v^2 = vo^2 + 2ax using g as a and everything else is pretty explanitory. Where'd I go wrong?