What Device Can Apply Constant Force Per Second for String Tension Experiments?

[mindboggling]

I'm looking for something that can pull on a string at a constant force per second

So that i can graph Force (n) over Time (s) just like that:

in this graph, the red line represents the tension of a string as i pull on it. However, i really need that slope to be constant.

By the I'm investigating how different force per second affects the breaking force of the string

From preliminary experiments, i observed that that:

the trough of the graph is when the string breaks.

The larger N/s applied, the string breaks at a higher tension
The lower N/s applied, the string breaks at a lower tension

WHY IS THIS SO? which equations can i use?

 

[Nate810]

The answer to your question lies in the properties of the string itself. The type of string, the diameter, and the material used will all determine how much force it can handle before breaking. Generally, the thicker and stronger the material, the higher the tension it can tolerate before breaking.So when you apply a constant force per second (N/s) to the string, the tension increases over time until it reaches the breaking point. This is because the force is being applied consistently, meaning the tension on the string is constantly increasing. As the tension increases, it eventually reaches a point where the string can no longer withstand it and breaks.You can calculate the needed N/s to break the string by using the equation: Breaking Force = Breaking Stress x Cross-sectional Area. This equation basically tells us that the amount of force needed to break the string is equal to the stress the string can handle multiplied by the cross-sectional area of the string.So, if you know the breaking stress for the material and the cross-sectional area of the string, you can calculate the force per second (N/s) that will cause the string to break. This will allow you to accurately graph the Force (N) over Time (s) and see the correlation between the two.

 

[m2003]

To achieve a constant force per second, you will need a device that can exert a steady force on the string. This can be achieved using a force sensor, such as a load cell, connected to a motor or other mechanism that can apply a consistent force to the string. The motor can be controlled to exert a specific force per second, allowing you to collect data on the tension of the string at different force rates.

To explain why the string breaks at a higher tension with a larger force per second, you can use the equation F=ma, where F is the force applied, m is the mass of the object (in this case, the string), and a is the acceleration. In this case, the acceleration is caused by the force being applied to the string. Therefore, with a larger force per second, the acceleration of the string will be greater, causing it to reach a higher tension before breaking.

Additionally, you can use the equation F=ke, where F is the force applied, k is the spring constant, and e is the elongation of the string. This equation shows that the tension of the string is directly proportional to the force applied to it. Therefore, with a larger force per second, the tension of the string will also be greater, leading to a higher breaking point.

Overall, by using a device that can exert a constant force per second and collecting data on the tension of the string at different force rates, you can create a graph that shows the relationship between force and time, and use equations such as F=ma and F=ke to explain why the string breaks at different tensions with different force rates.