FBD Help: Tension and Slowing Down

[woodrufs]

Homework Statement

First of all, thank you for taking your time to look at this. I cannot seem to figure it out!

http://screencast.com/t/MzZiNjhmMzUt

I may be completely wrong, but I feel like there isn't any tension... If the ship is slowing down, doesn't that mean that the string isn't fully stretched out...? I'm so confused!

Thank you.

Homework Equations

None? It's a FBD?

The Attempt at a Solution

I'm sure this is extremely hard to see but here are my attempts. I've tried them both in the same direction and everything...

http://screencast.com/t/MmNkMzM3

Thanks again for everyone's help!

 

[PhanthomJay]

Draw the FBD of the instrument. You do note that the 2 forces acting on it are its weight and the tension force in the hanging wire. Since it is given that the acceleration is slowing down the rocket's (and instrument's) velocity, what direction must the acceleration be in?? Then use Newton 2, noting that the net force must be in the same direction of the acceleration. Note also that tension forces always pull away drom the object on which they act. Crunch out the numbers to get the relative scale of the weight and tension forces. (There will always be some tension in the rope, unless the object is in free fall, in which case the wire goes slack (no tension)).

 

[woodrufs]

Yay! Thanks Jay! That helped me out and I got it right!


Thank you!

 

[PhanthomJay]

You are welcome. Wecome to PF!

 

[rwisz]

Hello,

Thank you for reaching out for help. I understand that you are having trouble understanding the concept of tension and slowing down in a Free Body Diagram (FBD). Let me try to explain it to you.

In a FBD, we represent all the forces acting on an object as arrows. These forces can be balanced or unbalanced. When an object is in motion, there are usually multiple forces acting on it, causing it to speed up, slow down, or maintain a constant speed.

In your example, the ship is slowing down. This means that there is an unbalanced force acting on the ship, causing it to decelerate. The force that is causing this deceleration is the tension in the string. The tension is the force that the string is exerting on the ship to slow it down.

Now, you may be wondering why there is tension if the string is not fully stretched out. This is because the string does not need to be fully stretched in order to exert a force. As long as there is some tension in the string, it will exert a force on the ship.

To represent this in a FBD, you would draw an arrow pointing in the opposite direction of the ship's motion, labeled as "tension". This arrow would be equal in magnitude to the force of friction acting on the ship, which is causing it to slow down.

I hope this explanation helps you understand the concept better. If you have any further questions, please do not hesitate to ask. Remember, you can always consult your textbook or ask your teacher for clarification. Good luck with your homework!