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1. ### Maximum possible momentum change in isolated system

This "push off" doesn't happen when ordinary objects like balls or rocks... collide? How do we find with help of kinetic energy formula, maximum possible change of momentum in an isolated system?
2. ### Maximum possible momentum change in isolated system

hello. If in isolated system two objects (one wih momentum 6 and the other with momentum 3)collide, total momentum of the system always remains the same (total_momentum=9). Depending on the mass, material of objects and some other variables, the change of momentum could vary. Does maximum...
3. ### I'm stuck.Really,really

But WHY does formula always give you the distance to the center of a mass ? So far I only have your word (and book's )that no matter where the axis is, the torque will always be as if the whole mass is at the center of mass
4. ### I'm stuck.Really,really

No, you misread my post. I already understood everything you explained! What I don't understand is how or why no matter where the axis is the magnitude of torque m*g*X is always as if the whole mass of a body is pulling from center of mass. I realize that X = (x_1 m_1 + x_2 m_2)/m always...
5. ### I'm stuck.Really,really

hello I'm learning about torques and got really stuck. I hope someone can take the time and help me out with this When calculating the torque caused by the weight of an object, no matter where we put the axis of rotation, the magnitude of torque m*g*X is always as if the whole mass of a...
6. ### Why does center of mass behave

What does a_{cm} mean? Acceleration of a part of an object that is 1 cm in length? If that is the case, then M\vec{r}_{cm} must mean torque of a part of the body that is 1 cm in length? Isn't that a formula for finding how far from the rotation axis a center of mass is? Aren't rotational...
7. ### Why does center of mass behave

Why when we throw an extended object like a baseball bat will the center of mass follow the same parabolic path that we expect for a smaller obeject like ball, while the bat itself will rotate around this ceneter of mass? Why does center of mass behave like a simpler object? thank you

10. ### Sum of all forces zero,but net torque not zero?

So a sum of all forces equals zero for a body standing still or moving with constant velocity , but still net torque may not be equal equal to zero ? I though there was a law saying something to the effect : "if an object is not pushed or pulled upon, or is standing still, then the sum of...
11. ### Sum of all forces zero,but net torque not zero?

hiya Newton's law says if an object is not pushed or pulled upon, its velocity will naturally remain constant, or body will remain standing still But is this only true if the sum of all torques is also zero? If we pull on wheel (its axis attached to something so it doesn't fall down )...
12. ### Elliptical Orbit Greetings: Exploring Gravitational Force

thanx So basicly you could still call a force acting on object going in elliptical motion a centripetal force, even if it is changing its magnitude?
13. ### Constant of gravitation-what is that?

I will read it thanx But I still am not shure how much of this stuff do I actually have to know ...meaning how deep must I go ( first year of high school ) ?
14. ### Elliptical Orbit Greetings: Exploring Gravitational Force

greetings If we throw an object in straight line this objects travels in parabolic path until it hits the ground. But in fact this parabola is only a part of an ellipse that object would travel in and center of the Earth is one of the foci points I understand that object can circle around...
15. ### Constant of gravitation-what is that?

interesting But how was G derived from kepler's formula F = 4*PI^2*K*m/r^2 by Newton?
16. ### Constant of gravitation-what is that?

A-I guess I'm missing the obvious here since I don't get why we need to put constant that shows tiny force inside F = m1*m2/r^2 formula in order to calculate forces between planets? B-I assume it was measured only recently (in the 20 century) , but still G was somehow derived from...
17. ### Constant of gravitation-what is that?

greetings Since I'm a beginner I hope the following questions can be exaplined layman's terms Newton's gravitational law says that F = G*m1*m2/r^2 G is called constant of gravitation, but what does this constant represent and what is its use in the above formula. And how did we...
18. ### Force following same rules as vectors

I had an impression that using vectors for net force was something immediatelly obvious and a common sense for most of you people. So basicly vectors are just a means to an end until someone finds other, more precise way of finding components of the force ?
19. ### Force following same rules as vectors

hiya I understand vectors perfectly, but still something is bothering me when it comes to forces being represented as vectors We'd compute the x component of force F with F*cos(alpha), alpha being angle force has with x axis. Promblem I have with this is why does force follow the same...
20. ### I can't study on untill I get this-please do help me

thanx a million. I really appreciate your help
21. ### I can't study on untill I get this-please do help me

So basicly force will "figure out" how much of its force must distribute over a rope to object m1 in order to accelerate m1 with a ? So if F is pulling on object on the right side,this object or force F will somehow figure out how much of force F must it distribute over to the left side of...
22. ### I can't study on untill I get this-please do help me

This I understand . I understand C example if I think ob both objects as one. But if I look at them separately, confusion arises. So net force redistributes itself between the two objects? How is that possible ? *In order to ask the following questions I must first understand question A ...
23. ### I can't study on untill I get this-please do help me

I can't study on until I get this--please do help me hello Perhaps a little introduction. I've quit high school 7 years ago and recently decided to finish it and as such I'm learning physics at home by myself. I hope you guys can answer all three questions in (gory details) since they are...