Hooke's Law

Part of the Mechanics section of Coddy's Physics journey. Lesson 54 of 94.

A stretched spring pulls back toward its natural length; a squeezed one pushes back. Hooke's law:

F = k x

x is the stretch or squeeze in metres, k the spring constant in N/m.

The spring force always points back toward the natural length.

A block on the floor attached to a wall by a spring with constant k, pulled a distance x to the right of the natural length, marked x = 0; the spring force F = kx on the block points left, back toward the natural length

Stretched by x, the spring pulls the block back toward x = 0.

A spring holding a mass at rest: kx = mg.

Challenge

A 2 kg mass hangs at rest from a spring and stretches it 0.08 m. Find the spring constant k.

Try it yourself

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Mechanics

1Vectors and Newton's Laws

Right Triangles What is a Vector?Adding Vectors Axes and Directions Vector Components Forces Around Us Friction and Tension Newton's First Law Newton's Second Law Newton's Third Law Recap - Net Force

4Kinematics in 1D

Position and Displacement Velocity Acceleration Motion Graphs Equations of Motion Recap - Braking Car

7Kinematics and Newton

From Forces to Motion From Motion to Forces Two-Stage Motion Recap - Elevator

10Springs

Hooke's LawSprings in Series Springs in Parallel Recap - Spring Scale

13Momentum in 2D

Momentum as a Vector 2D Collisions Explosions Recap - Billiards

16Gravitation

Law of Gravitation Gravity and Altitude Satellites Kepler's Laws Gravitational Energy Escape Velocity Satellite Energy Recap - Mission to Orbit

2Friction

What is Friction?Static Friction Kinetic Friction Friction and Newton's Laws Recap - Sliding Crate

5Vertical Motion

Free Fall Throwing Upward Time in the Air Recap - Dropped Ball

8Project: Delivery Drone

Mission Briefing Takeoff Thrust Climb to Altitude Cruise and Brake Package Drop

11Elastic Energy

Elastic Potential Energy Spring Launchers Energy with Springs Recap - Spring Launcher

14Circular Motion

Uniform Circular Motion Centripetal Acceleration Horizontal Circles Vertical Circles Loop the Loop Recap - Car on a Curve

17Final Challenges

Recap - Stunt Ramp Recap - Crash Test Recap - Space Probe

3Inclined Planes

Forces on an Incline Gravity Components Frictionless Incline Incline with Friction Will It Slide?Recap - Ramp Challenge

6Projectile Motion

Independent Axes Horizontal Launch Launch at an Angle Range and Max Height Recap - Hit the Target

9Work and Energy

Work Kinetic Energy Work-Energy Theorem Gravitational PE Conservation of Energy Power Recap - Roller Coaster

12Impulse and Momentum

Momentum Impulse Conservation of Momentum Elastic Collisions Inelastic Collisions Recap - Air Track

15Simple Harmonic Motion

What is SHM?Mass on a Spring The Pendulum SHM Graphs Energy in SHM Recap - Oscillator