h t t p : / / w w w . j i s k h a .c o m / d i s p l a y . c g i ? i d = 1 25 2 8 8 8 9 2 9

ok hmmm

m2 g = m1 (acceleration radial)

so then if this is the correct equation my question... is how do you know when to consider the masses as a system and when not to?

net force = mass times acceleration

by deffintion
it dosen\'t mean this necessarily

net force = net mass times acceleration

when do I know when I should use the net mass and when not to as I have gotten points taken off before because i didn\'t use the net mass and am not sure when to consider the masses as one system and when not to...

like how come this is wrong

net force radial = (m1 + m2) (acceleration radial) = force of gravity on m2

and this is right

net force radial = m1 (acceleration radial) = force of gravity on m2

I need help on when to make this distinction between the masses and when not to as I don\'t know when i should...

THANKS!!!
This has been eating me away and I need to know this or the whole problem is wrong so it\'s important that I know when to make this distinction and when not to. So can you tell me when I should and when I shouldn\'t???

To determine when to consider masses as a system or not, you need to assess whether the forces acting on each mass are internal or external to the system.

- If the forces acting on the masses are external, then you should consider the masses as separate systems. In this case, you would use the individual masses in the equations.
For example, if m1 and m2 are experiencing external forces, such as forces applied by external objects, then you should treat them as separate system and use their individual masses.

- If the forces acting on the masses are internal, meaning they are caused by the interaction between the masses themselves, then you should consider them as one system. In this case, you would combine the masses together and use the total mass in the equations.
For example, if m1 and m2 are attracting each other through gravitational force, then you should treat them as one system and combine their masses.

Now, let's address your specific examples:

1. net force radial = (m1 + m2) (acceleration radial) = force of gravity on m2
This equation is incorrect because it assumes that both m1 and m2 are involved in producing the net force. However, in the context of the problem, only m1 should be considered as it is the one causing the acceleration radial. The force of gravity on m2 should be calculated separately using the individual mass of m2.

2. net force radial = m1 (acceleration radial) = force of gravity on m2
This equation is correct because it correctly identifies that the net force radial is caused by m1, so we use its mass in the equation. The force of gravity on m2 is calculated separately using m2's individual mass.

To determine whether to treat masses as one system or separate systems, carefully analyze the forces acting on them. Identify if the forces are internal or external, and then choose the appropriate approach. Consider what is causing the acceleration or the net force in the problem.

To determine when to consider the masses as a system and when not to, you need to examine the specific problem you are trying to solve.

In general, you should consider the masses as a system when they are exerting forces on each other, and their motions are interdependent. This means that the masses are connected or interacting in some way, and the forces they exert on each other affect their overall acceleration. In such cases, it is appropriate to use the concept of a "net mass" or the total mass of the system.

On the other hand, if the masses are not interacting or their motions are independent of each other, you can treat them as separate entities and use individual masses instead of the net mass. This would be the case when the masses are not connected, or if they are far apart from each other such that their gravitational interaction is negligible.

Regarding your examples:

The equation you mentioned, m2g = m1 (acceleration radial), suggests that the two masses are connected or interacting in some way, and their relative motion affects their acceleration. In this case, it would be appropriate to consider the masses as a system and use the net mass (m1 + m2) when calculating the net force.

However, if the masses are not interacting and their motions are independent, then you should treat them as separate entities. In the second equation you provided, net force radial = m1 (acceleration radial) = force of gravity on m2, it seems like the two masses are not connected or interacting. Here, it is appropriate to consider m1 and m2 separately and use the individual masses in the equation.

In summary, to determine when to consider the masses as a system and when not to:
- Check whether the masses are connected or interacting.
- Assess if their motions are interdependent and affect each other's acceleration.
- If they are connected, use the net mass or total mass of the system.
- If they are not connected or their motions are independent, treat them as separate entities and use the individual masses.