Register to reply

Escape Velocity

by SoccaCrazy24
Tags: escape, velocity
Share this thread:
Nov16-05, 11:05 AM
P: 25
Consider a spherical asteroid with a radius of 5 km and a mass of 8.65x10^15 kg.
(a) What is the acceleration of gravity on the surface of this asteroid?
ANSWER: ___ m/s2
(b) Suppose the asteroid spins about an axis through its center, like the Earth, with an angular speed . What is the greatest value can have before loose rocks on the asteroid's equator begin to fly off the surface?
ANSWER: ___ rad/s

For (a) which I got right.... I used the equation g=(G*M)/R^2
g=(6.67e-11*8.65e15)/(5000^2)=.023078 m/s2

For (b) I used the equation Wf^2= Wi^2 + 2*a*d and i substituted the numbers in to get... Wf^2 = 0 + 2(.023037*2pi)(31415.9m*2pi) and I got it to be 95.45 rad/s and for some reason this is not right... am I even using the right equation or is there another equation i can use to get the answer such as maybe... F= (G*M*m)/R^2 ....
Phys.Org News Partner Science news on
Experts defend operational earthquake forecasting, counter critiques
EU urged to convert TV frequencies to mobile broadband
Sierra Nevada freshwater runoff could drop 26 percent by 2100
Nov16-05, 11:34 AM
HW Helper
P: 481
I've got no idea what you've done in (b), but have you taken gravity into account at all?

I'd use centrifugal force.
Nov16-05, 11:35 AM
P: 183
Consider that, in circular motion:


If a > g, then what would happen?

Does this help you?


Nov16-05, 02:16 PM
P: 25
Escape Velocity

so you are saying a =w^2 * r..... so w = sqroot(a/r) so w= sqroot(.023037/5000) = .0021465 ?????
Nov16-05, 05:15 PM
P: 6
i already tried that method greg and i got the wrong not liking this topic at all lol

Register to reply

Related Discussions
Escape Velocity General Physics 4
Escape velocity help! General Physics 18
Escape velocity Special & General Relativity 5
Escape Velocity Introductory Physics Homework 3
Escape velocity Astronomy & Astrophysics 2