Spring Potential Energy Calculator
Works out the energy held in a stretched or compressed spring.
Answer
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Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
Stored energy —
Spring constant — N/m
Extension or compression —
Spring force at that point —
Launch speed of the mass —
Assumes —
The formula
E = ½ k x²
The force grows steadily with stretch, so the energy is the average force times the distance.
What to watch out for
Energy rises with the square of the stretch, so double the compression holds four times the energy.
Frequently Asked Questions
How much energy is in a 500 N/m spring compressed 10 cm?
2.5 J. At 20 cm it is 10 J.
How fast would that launch a 100 g mass?
Up to 7.07 m/s.