Question

please help keep getting these wrong

(a) What is the escape speed on a spherical asteroid whose radius is 515 km and whose gravitational acceleration at the surface is 2.7 m/s2?
3.0147E9

Incorrect: Your answer is incorrect.
m/s
(b) How far from the surface will a particle go if it leaves the asteroid's surface with a radial speed of 1000 m/s?
1.0736x10^22

Incorrect: Your answer is incorrect.
Your answer cannot be understood or graded. More Information m
(c) With what speed will an object hit the asteroid if it is dropped from 1000 km above the surface?
2083.27

Incorrect: Your answer is incorrect.
m

Answer 1

I would like to see your work to understand what you did.
a) PE=KE leads to
mMG/R=1/2 mV^2
v=sqrt(2*M*G/R)=sqrt(2*Mass*G)/R
but g=GMass/R^2 so or G*Mass=g*R^2
v= sqrt(2*2.7 *5.15e5) = not your answer.