| Author |
Message |
![[Post New]](/templates/default/images/icon_minipost_new.gif) 2 Dec 2007 20:17:23 IST
|
|
|
When a particle is projected up. its velocity decreases so its momentum decreases...does this not violate conservation of momentum principle?
|
<TABLE CELLSPACING="1" CELLPADDING="1" BORDER="0">
<TR><TD>
        
<DIV ALIGN="right">Glitter Graphics</DIV></TD></TR></TABLE>
|
|
|
|
2 Dec 2007 20:30:19 IST
|
|
|
Hi Freind, Well you are saying that when a ballm is thrown up its velocity decreases and hence its momentum also. But "Law Of Conservation of Linear Momentum" is applied only when there is no force acting. While here Gravitational Force would be acting.
|
Santosh |
this reply: 5 points
(with 1 
in 1 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
2 Dec 2007 20:33:08 IST
|
|
|
as santosh rightly said here gravity is acting hence colm can't be applied
|
"Imagination is more important than knowledge."
|
this reply: 0 points
(with 0
in 0 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
2 Dec 2007 20:36:05 IST
|
|
|
exactly ...
external force acts here.........
man this dial up connection is so slow..... i was about to answer first.... but waited for exactly 4 minutes to have this page opened and saw santosh has already answered...
|
salman khan |
this reply: 0 points
(with 0
in 0 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
2 Dec 2007 20:38:53 IST
|
|
|
Hey Tarun,
All the above replies are correct.
You can conserve momentum when you consider particle and earth as a system. Then gravitational force becomes internal force.
IN that case when momentum of particle decreases, momentum of earth increases but as mass of earth is very huge, the change in earth's velocity is not noticeable.
Hope you understood.
|
The quality of a person's life is in direct proportion to their commitment to excellence, regardless of their chosen field of endeavor.
It is during our darkest moments that we must focus to see the light.
Check out my blog at:
http://tarinbansal.blogspot.com/
(A must see for every student)
Back to goiit, this time with Baby Veerappan. :D |
this reply: 7 points
(with 1
in 2 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
2 Dec 2007 20:47:55 IST
|
|
|
Law of conservation of linear momentum states: if Fext=0., then linear momentum remains conserve........ If we consider only particle as system , then gravitational force is external and so..........linear momentum does not remain constant...... and If you consider gravitational force as internal force,then both earth and the mass has to be consider as single system ......so.linear momentum of system remains constant...........if particle goes up then momentum of particle decrease.....and momentum of earth increases.......but mass of earth is so large that its velocity produced is very small that it can be neglected............... rate if satisfied!!!!!!!!!!!!!!!
|
my future signature:
LOKESH SARDANA,
department of Production and Industrial engineering,
Indian Institute of Technology,Roorkee.
Happiness can be found, even in the darkest of times, if one only remembers to turn on the light.
Albus Dumbledore
Harry Potter and the Prisoner of Azkaban movie
There are only two ways to live your life. One is as though nothing is a miracle. The other is as though everything is a miracle.
-- Albert Einstein
|
this reply: 7 points
(with 1
in 2 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
2 Dec 2007 20:48:23 IST
|
|
|
1 more thing i ll lik to tell u iz that this earth frame or "inertial frame" to b precise.. all the laws related to kinematics r considered true 4 inertial frame, hope it's useful for u.
|
this reply: 0 points
(with 0
in 0 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
2 Dec 2007 22:02:35 IST
|
|
|
LAW of conservation of linear momentum clearly reinstates the pre-requisite that no external force is acting upon the system, whereas gravitational force is existent here.
|
---------------------------------------------------------------
* Gaurav Ragtah ( aka Artemis Fowl )
* Agent 'G' [sniper] - SD-6 (Alliance of Twelve)
* Your friendly, neighborhood spideyunlimited |
this reply: 0 points
(with 0
in 0 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
|
|
Moderation Team
![[Up]](/templates/default/images/icon_up.gif "[Up]"){kind=icon}
