Forces and getting acceleration of two objects

AI Thread Summary
The discussion centers on calculating the acceleration of two objects connected by a massless string over a frictionless pulley. One object has a mass of 5 kg hanging vertically, while the other, with a mass of 10 kg, is on a 30-degree incline with a coefficient of kinetic friction of 0.205. The user outlines their method for determining the forces acting on both objects, setting up equations for the forces in the vertical and horizontal directions. They confirm that their approach is correct, given that the incline is downhill. The conversation highlights the importance of correctly applying the forces based on the direction of the incline.
madinsane
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Okay so their are two objects attached together by a massless string and a frictionless pulley. One of them is hanging vertically with mass 5kg the other one is on an incline that makes a 30 degrees angle with the horizontal and is of mass 10 the coefficient of kinetic friction of the incline on the object is 0.205 an they are asking us to get the acceleration

For my solution
I got the total forces in the y direction for object 1 to be mg-T=ma
So (5)(9.8) -T=5a
So T=-5a+(5)(9.8)

For the second I got total f in x as
T+mgsin30-friction=ma
T+(10)(9.8)sin30-(10)(9.8)cos(30)(0.205)=10a
Then I equated the two equations and got a
Is my method cOrrect[/QUOTE]
 
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hi madinsane! :smile:
madinsane said:
Is my method cOrrect
if the incline is downhill, then yes :smile:

(if it was uphill, of course, you'd need minus mgsin30°)
 
tiny-tim said:
hi madinsane! :smile:

if the incline is downhill, then yes :smile:

(if it was uphill, of course, you'd need minus mgsin30°)


thanks, yes it was downhill :)
 
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