Spring Constant Calculator
Hooke's law force, extension and energy.
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Results
- Force
- 30 N
- Stored energy
- 1.8 J
- Extension under mass
- 0.1177 m
- Oscillation period
- 0.688 s
Quick answer
Hooke's law says force is proportional to extension for an ideal spring.
F = kx; E = ½kx²
How to use the Spring Constant Calculator
- 1Enter the spring constant in N/m.
- 2Enter the extension or compression.
- 3Add a mass to see static deflection and period.
Frequently asked questions
Does Hooke's law always hold?
Only below the elastic limit — beyond it the spring deforms permanently.
How do I measure k?
Hang a known mass and divide its weight by the extension.