Natural Frequency Calculator Formula

Understand the math behind the natural frequency calculator. Each variable explained with a worked example.

Formulas Used

Angular Natural Frequency

omega_n = sqrt(spring_k / mass)

Natural Frequency

freq_hz = sqrt(spring_k / mass) / (2 * pi)

Natural Period

period = 2 * pi / sqrt(spring_k / mass)

Variables

VariableDescriptionDefault
spring_kSpring Stiffness (k)(N/m)10000
massMass (m)(kg)5

How It Works

Natural Frequency of a Spring-Mass System

Every elastic system has a natural frequency at which it tends to vibrate when disturbed.

Formulas

omega_n = sqrt(k / m) (angular frequency in rad/s)

f_n = omega_n / (2 pi) (frequency in Hz)

T = 1 / f_n = 2 pi / omega_n (period in seconds)

Resonance occurs when the excitation frequency matches the natural frequency, leading to large amplitude vibrations that can cause structural failure.

Worked Example

A 5 kg mass on a spring with stiffness 10,000 N/m.

spring_k = 10000mass = 5
  1. 01omega_n = sqrt(10000 / 5) = sqrt(2000) = 44.72 rad/s
  2. 02f_n = 44.72 / (2 x 3.1416) = 7.12 Hz
  3. 03T = 1 / 7.12 = 0.1405 s

Ready to run the numbers?

Open Natural Frequency Calculator