Newton's Escape Velocity (1 Viewer)

[serge]

Newton's idea was that escape velocity is the minimum speed
needed to leave a planets orbit, right?

(is this statement correct, or have i missed an important term?)

 

[Ghost1788]

Escape velocity according to Newton is the minimum velocitry required to escape the gravitational attraction of a object in space, usually refered to as a planet ...

 

[serge]

but isnt there always a gravitational attraction between every mass?

(like you're attracted gravitationally to your computer...
but you're much more attracted to the earth so you cant tell?)

 

[Ghost1788]

but isnt there always a gravitational attraction between every mass?

technically yes

but on mass such as a computer the gravitational attraction is so minute that it is
Ignored

Technically u are affected by the gravitational field of all the stars, blackholes etc in
the universe

However because u are closer to the earth..the closest large body of mass you are
most affected by its gravitational attraction

If an object is projected upward with a large
enough velocity it can escape the gravitational
pull of the Earth(or other planet) an go into
space. The necessary velocity to leave the eartrh
(or other planet) is called escape velocity

 

[serge]

i get it, cool

(I just hope those HSC markers dont get technical)

 

[Ghost1788]

lol
they wont if newton and all them smart scientist people desided to go 'technical' in their equations every time you had to do an equation you would need to calculate the relative strength of each body of mass in the universe...even then 'this technical' detail would barely alter the answer of equations relating to gravity Therefore it is relatively safe for us to ignore them at our level at least...

 

[helper]

At you approach an infinite distance away, you approach a point with no gravitational force and no gravitational field strength. It is this point that Newtown was using when he is talking about escape velocity.