Tension in the toy string

In summary: But yes, in the static method, we attached the spring scale to the hook where the string was attached and pulled horizontally to the radius. This gave us the horizontal component of the tension, which we then used in the calculation with the angle to find the total tension in the string.
  • #1
ys2050
18
0
we hung a toy pig from the ceiling with a string and when turned on, it traveled in a circle.
We figured out the tension in the string using dynamic and static method...
in dynamic we just used the measured radius and found out the angle to calculate the force of tension.
in static, we measured the horizontal force by attaching the spring scale's hook to the hook where the string was hooked on. We pulled the apparatus horizontally to the radius. With this and the angle we calculated the force of tension.

My question is...
What is the difference in the result of the two methods?
Why is one called dynamic and the other, static?
Why do I get a slightly different tensions for the two methods?? What's the cause of the discrepancy?

Any help would be appreciated. :)
 
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  • #2
ys2050 said:
… and when turned on …

in static, we measured the horizontal force by attaching the spring scale's hook to the hook where the string was hooked on. We pulled the apparatus horizontally to the radius.

Hi ys2050 :smile:

I love your flying pig! :smile:

(Did you ever work out why it wouldn't go backwards?)

Can you tell those of us who haven't seen it:

What do you mean by "turned it on" - where is the motor, and what does it do?

In the static case, I'm not getting it … what position did you pull the pig to, and what connection does that have to the dynamic case? :smile:
 
  • #3
http://www.otherlandtoys.co.uk/flyingpig2_500.jpg
?
 
  • #4
… just like in nature …

Thanx, acolavin! :smile:

ooh … I see it "has a realistic flying motion" …

hmm … how do they know? :smile:
 
  • #5
tiny-tim said:
Hi ys2050 :smile:

I love your flying pig! :smile:

(Did you ever work out why it wouldn't go backwards?)

Can you tell those of us who haven't seen it:

What do you mean by "turned it on" - where is the motor, and what does it do?

In the static case, I'm not getting it … what position did you pull the pig to, and what connection does that have to the dynamic case? :smile:

I pulled the pig horizontally to its radius and the spring scale showed the horizontal force. I used that and the angle to figure out the tension of the string, which is the hypotenuse.
In the dynamic method, I used the formula T = mg / cos(theta)
In the static method, I used T = Fc / sin(theta), where Fc is the horizontal force.
and no... i still don't know why it can only fly in one way...
 
  • #6
ys2050 said:
I pulled the pig horizontally to its radius and the spring scale showed the horizontal force. I used that and the angle to figure out the tension of the string, which is the hypotenuse...

No, the spring scale will show the tension in the string, not the horizontal componet.

CS
 
  • #7
stewartcs said:
No, the spring scale will show the tension in the string, not the horizontal componet.

CS


but in the handout, it says:
" Holding the other end of the spring scale, horizontally pull it out to its radius when it was flying around in a circle. Note this reading down and calculate the tension in the string."

If the spring scale does measure the tension of the string, why would you need to do any calculation?!
 
  • #8
ys2050 said:
but in the handout, it says:
" Holding the other end of the spring scale, horizontally pull it out to its radius when it was flying around in a circle. Note this reading down and calculate the tension in the string."

If the spring scale does measure the tension of the string, why would you need to do any calculation?!

If you pull on a string that is connected to a spring scale that is fixed to an articulated point, then the reading on the scale at that moment is the tension in the string.

However, I misunderstood what you were looking for. I believe that you are looking for the tension in the string the moment the pig was flying and trying to calculate it based on the tension you just measured in the horizontal direction while pulling the pig out to the radius of flight...right?

CS
 
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  • #9
… spring horizontal … ?

stewartcs said:
No, the spring scale will show the tension in the string, not the horizontal componet.

Ah, but I think ys2050 is holding the spring horizontally, so as not to interfere with the vertical component of the tension (so that it still matches the weight of the pig).

He therefore does measure only the horizontal component of the tension, and has to make a calculation to get the full tension.

Is that right, ys2050? :smile:
 
  • #10
tiny-tim said:
Ah, but I think ys2050 is holding the spring horizontally, so as not to interfere with the vertical component of the tension (so that it still matches the weight of the pig).

He therefore does measure only the horizontal component of the tension, and has to make a calculation to get the full tension.

Is that right, ys2050? :smile:

That's what I just said.

CS
 
  • #11
I think your previous response could be misinterpreted.
stewartcs said:
If you pull on a string that is connected to a spring scale that is fixed to an articulated point, then the reading on the scale at that moment is the tension in the string.
In the "static" case, the spring scale is attached to the pig, not the string on which the pig is hanging. So the scale reading is not the tension in the string (at least not that string).
 
  • #12
Doc Al said:
I think your previous response could be misinterpreted.

In the "static" case, the spring scale is attached to the pig, not the string on which the pig is hanging. So the scale reading is not the tension in the string (at least not that string).

Sorry, I thought I had made that clear by not mentioning a pig anywhere in the system.

The way I interpreted the measurement method was that the pig was removed and the spring scale was attached to the ceiling hook, then a string was attached to the spring scale and pulled to the radius of where the pig was flying.

I can't believe I'm talking about flying pigs. :rofl:

CS
 
  • #13
stewartcs said:
The way I interpreted the measurement method was that the pig was removed and the spring scale was attached to the ceiling hook, then a string was attached to the spring scale and pulled to the radius of where the pig was flying.
Perhaps it wasn't clear from this thread (he has another thread on the same topic :mad:), but he's measuring the same tension via two different methods. In both methods, the pig is there.
I can't believe I'm talking about flying pigs. :rofl:
You've got to believe!
http://keithcombs.members.winisp.net/flyingpig.gif
 
Last edited by a moderator:
  • #14
… ooh look … there's another one … !

stewartcs said:
The way I interpreted the measurement method was that the pig was removed …

A flying pig without the pig … is like a grin without the cheshire cat! :biggrin:

Never ignore the flying pig!

Those who ignore flying pigs …

:rofl: are pig-ignorant! :rofl:​
I can't believe I'm talking about flying pigs. :rofl:

Would you believe … they're talking about you? :smile:
 

1. What causes tension in a toy string?

Tension in a toy string is caused by the application of a force or weight at one or both ends of the string. This force pulls the string taut, creating tension.

2. How does the material of the toy string affect tension?

The material of the toy string can affect tension in several ways. A stronger or more rigid material will be able to withstand greater tension before breaking. Additionally, the elasticity of the material can affect how much tension it can withstand before stretching or snapping back to its original shape.

3. Can the length of the toy string affect tension?

Yes, the length of the toy string can affect tension. A longer string will typically have less tension than a shorter string under the same force or weight. This is because the longer string has more surface area to distribute the force, resulting in less tension overall.

4. How can tension in a toy string be measured?

Tension in a toy string can be measured using a device called a tension meter, which measures the amount of force pulling on the string. Tension can also be estimated by observing the amount of stretch or deformation in the string under a given weight or force.

5. What are the potential dangers of high tension in a toy string?

High tension in a toy string can pose a safety hazard, as it can cause the string to snap or break. This can result in the toy or any attached objects to fly through the air, potentially causing injury. It is important to always use caution and follow safety guidelines when playing with toys that involve tension in a string.

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