Restoring force
The spring force always points back toward the equilibrium position.
Physics Learning Tool
Hooke's Law Spring Motion Simulator
Pull or compress a spring and see how force, acceleration, period, and energy change.
Big idea: A spring pulls back toward its resting position. The farther you stretch or compress it, the stronger the restoring force becomes.
Interactive spring lab
Change the spring constant, mass, starting displacement, and damping. Then start the motion to watch the spring oscillate.
50 N/m
1.0 kg
12 cm
Low
Displacement x0.12 m
Spring force F-6.00 N
Acceleration a-6.00 m/s²
Period T0.89 s
F = -kxThe minus sign means the force points back toward the resting position.
T = 2π√(m/k)A heavier mass gives a longer period. A stiffer spring gives a shorter period.
What to notice
Stretch the spring farther and the restoring force becomes stronger. When motion starts, energy trades between spring potential energy and kinetic energy.
What students should remember
More stretch, more force
If displacement doubles, the spring force also doubles.
Motion pattern
With little damping, the mass moves back and forth in simple harmonic motion.
Practice keywords
Use this tool to explore Hooke's Law, spring motion, spring constant, restoring force, displacement, simple harmonic motion, period, and damping.
Hooke's Lawspring motionF = -kxrestoring forcesimple harmonic motionspring constant