Calculator Input
Enter any two of force, spring constant, and extension. Initial length is optional.
Example Data Table
| Case | Force (N) | Spring Constant (N/m) | Extension (m) | Energy (J) | Initial Length (m) | Final Length (m) |
|---|---|---|---|---|---|---|
| Spring A | 10 | 200 | 0.05 | 0.25 | 0.20 | 0.25 |
| Spring B | 25 | 500 | 0.05 | 0.625 | 0.30 | 0.35 |
| Spring C | 40 | 1000 | 0.04 | 0.8 | 0.15 | 0.19 |
| Spring D | 5 | 250 | 0.02 | 0.05 | 0.10 | 0.12 |
Formula Used
Hooke's law: F = k × x
Extension: x = F / k
Spring constant: k = F / x
Elastic potential energy: U = 0.5 × k × x²
Final length: Lfinal = Linitial + x
Positive extension usually means stretching, while negative extension represents compression. The relation holds best within the elastic limit of the material or spring.
How to Use This Calculator
- Enter any two among force, spring constant, and extension.
- Select the correct unit for each entered value.
- Optionally add an initial length to compute final length.
- Choose how many points you want in the graph.
- Press the calculate button to display results above the form.
- Review the graph, summary table, and consistency check.
- Download the result as a CSV file or PDF report.
FAQs
1. What does Hooke's law describe?
Hooke's law describes the linear relation between force and deformation in an elastic spring or material. It states that force is proportional to extension within the elastic range.
2. Can I use compression values here?
Yes. Enter a negative extension value to represent compression. The calculator will produce a corresponding negative force when the spring constant remains positive.
3. Why do I need only two main inputs?
Because Hooke's law links force, spring constant, and extension. Once any two are known, the third can be found directly from the governing equation.
4. What is elastic potential energy?
Elastic potential energy is the energy stored in a spring during deformation. It depends on stiffness and the square of extension, so doubling extension increases stored energy strongly.
5. What happens if I enter all three values?
The calculator compares your entered force against the force predicted by stiffness and extension. It then reports the residual and percentage error for a quick consistency check.
6. Does this law work for every material?
No. It works best only within the elastic region, where deformation remains proportional to force. Beyond that range, many materials stop behaving linearly.
7. Why is spring constant required to stay positive?
A normal passive spring resists deformation, so its stiffness is positive. Negative stiffness would represent a very different and unstable physical behavior.
8. What units can I use in this tool?
You can use newtons, kilonewtons, and pound-force for force; several stiffness units; and meters, centimeters, millimeters, or inches for length values.