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Library / Foundations: Physics / FPH-20

Foundations: Physics

Period of a mass on a spring

Time for one oscillation of a mass on a spring.

Ref
FPH-20
Rev
v1
Field
Foundations: Physics
Result
T [s]

Light spring and negligible damping. m in kg, k in N/m, T in s.

Heavier masses oscillate more slowly; stiffer springs oscillate faster.

Calculator

Solve for
s
kg
0.01100
N/m
110,000
  • Frequency3.183 Hz
  • Angular frequency20 rad/s

What drives the result

Each variable is moved across its typical range while the others stay at the values above. The longest bar is the key driver.

Period (s) current value 0.3142 s
mMassKey driver
0.04444.44
kSpring constant
0.04444.44
  • The period does not depend on the amplitude (for small oscillations).
  • Quadrupling the mass doubles the period.
Chart data as tables

Ranked variables

VariableTypical rangeLowest resultHighest resultSwing (s)Local stepChange in result
m Mass0.01 to 100 kg0.044434.4434.398+10%+4.88 %
k Spring constant1 to 10,000 N/m0.044434.4434.398+10%−4.65 %

Sweep of Mass

Mass (kg)Period (s)
0.010.04443
0.031620.07901
0.10.1405
0.31620.2498
10.4443
3.1620.7901
101.405
31.622.498
1004.443

Sweep one variable

Period (s)Hover, touch, or use the arrow keys on the chart
01234 0.010.1110100 Mass (kg), log scale now 0.3142

Variables and how each one contributes

T

Period

Result · s

What the equation gives you. Everything else feeds it.

m

Mass

kg · typical 0.01 to 100

Oscillating mass. Raises the period with the square root.

k

Spring constant

N/m · typical 1 to 10,000

Spring stiffness. Lowers the period with the square root.

Worked example with the values above

  1. m/k = 0.5 / 200 = 0.0025.
  2. Square root: 0.05.
  3. T = 2π × 0.05 = 0.3142 s.

Assumptions and limits

  • Light spring, no damping.
  • Hooke’s law holds.

Common mistakes

  • Using the spring mass as well as the load without correction.
  • Forgetting the 2π.

Statistics and uncertainty

Timing 10 oscillations and dividing by 10 reduces the timing error on T by ten.

Where it is used

  • Instrument and equipment mounts.
  • Suspension design.

Maths you need

  • Hooke’s law: F = kx
  • Square roots: √(m/k)

Related formulas

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