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# how do you know the direction of tension (M1) watch

1. Hey so quick question. So i know friction is always in the opposite direction to motion but how do i know what direction tension will be going?
2. (Original post by Appazap)
Hey so quick question. So i know friction is always in the opposite direction to motion but how do i know what direction tension will be going?
Opposite direction to the weight? i mean if oyu have a weight dangling off the edge of a table then tension is going to act in the opposite direction to the weight of the object right? because the tension holds the string together
3. (Original post by will'o'wisp2)
Opposite direction to the weight? i mean if oyu have a weight dangling off the edge of a table then tension is going to act in the opposite direction to the weight of the object right? because the tension holds the string together
Yeah i guess that applies to a smooth pulley. What about if an object is on a table and is being upwards or horizontally
4. (Original post by Appazap)
Yeah i guess that applies to a smooth pulley. What about if an object is on a table and is being upwards or horizontally
i'm not quite sure i understand?
5. (Original post by will'o'wisp2)
i'm not quite sure i understand?
So in the example above, what direction would tension be if that force applied was a string moving the block upwards
6. (Original post by Appazap)

So in the example above, what direction would tension be if that force applied was a string moving the block upwards
usually i work it out by mentally going through the method of calculation

so if tension goes down that string, you not calculating anything because you can't resolve upwards xD

so then it has to go up that string right?

i guess in a way pull on the string in the direction of that arrow on the diagram puts tension on the string in that direction

Edit:https://www.thestudentroom.co.uk/forumdisplay.php?f=38 <----post here because it's the official matsh forum and everyone not just me can help you
7. (Original post by will'o'wisp2)
usually i work it out by mentally going through the method of calculation

so if tension goes down that string, you not calculating anything because you can't resolve upwards xD

so then it has to go up that string right?

i guess in a way pull on the string in the direction of that arrow on the diagram puts tension on the string in that direction

Edit:https://www.thestudentroom.co.uk/forumdisplay.php?f=38 <----post here because it's the official matsh forum and everyone not just me can help you
Okay i will thank you
8. Hey so quick question. So i know friction is always in the opposite direction to motion but how do i know what direction tension will be going?
9. (Original post by Appazap)
Hey so quick question. So i know friction is always in the opposite direction to motion but how do i know what direction tension will be going?
When you're considering forces acting on an object, which is being pulled by a rope (or something that has tension in it), then the tension will be going in the same direction as the rope.

Do you have an example you're confused on?
10. (Original post by RDKGames)
When you're considering forces acting on an object, which is being pulled by a rope (or something that has tension in it), then the tension will be going in the same direction as the rope.

Do you have an example you're confused on?
so in this example for m1 the tension is towards the pulley and for m2 the tension is also towards the smooth pulley
11. (Original post by Appazap)
so in this example for m1 the tension is towards the pulley and for m2 the tension is also towards the smooth pulley
The first thing to understand is that tension is the same throughout the rope, and it is dependent on the weights of the two solids in the system of pulleys.

Secondly, the direction of the tension depends on which object you are considering forces on. If you consider all the forces acting on , then well you have the basic weight, the reaction force, maybe the friction, but there is also tension going to the right because at the other end of the rope there a second object which is under the influence of gravity so, it creates tension in the rope which wants to drag to the right.

Then if you consider , then as I said, you have the weight component, and the rope. The tension is going up here because the other end is attached to object which is resisting motion due to friction, thus adding that force upwards on to prevent it from free-falling down.
12. (Original post by RDKGames)
The first thing to understand is that tension is the same throughout the rope, and it is dependent on the weights of the two solids in the system of pulleys.

Secondly, the direction of the tension depends on which object you are considering forces on. If you consider all the forces acting on , then well you have the basic weight, the reaction force, maybe the friction, but there is also tension going to the right because at the other end of the rope there a second object which is under the influence of gravity so, it creates tension in the rope which wants to drag to the right.

Then if you consider , then as I said, you have the weight component, and the rope. The tension is going up here because the other end is attached to object which is resisting motion due to friction, thus adding that force upwards on to prevent it from free-falling down.
ahh i see

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