How to Use

Planetary Orbit Simulator – Gravitation, Ellipse, Kepler's Laws

Drag across the screen to set the launch speed and direction, then release to send the planet on its way. Pull weakly and it drops into a tight ellipse; pull hard enough and it leaves the star for good.

Uniform acceleration

Projectile motion

Friction

Leaning ladder

Pulley

Roller coaster

Conservation of momentum

Collision

Circular motion

Spring pendulum

Simple pendulum

Planetary orbit

Uniform Acceleration Simulator Slope is acceleration, area is displacement You can solve it without the time A negative acceleration is not always a slowdown Falling and throwing upward are one motion

Projectile Motion Simulator Horizontal and vertical move separately What disappears is the time The farthest throw is at 45°

Friction Simulator Friction does as it is told It is set by how hard the surface is pressed The angle of slipping does not depend on weight

Leaning Ladder Simulator Balanced forces can still topple it The wall is smooth, the floor is rough The more upright, the safer

Pulley Simulator Add the equations and the tension goes Tension is not the weight It takes weight to get it moving

Roller Coaster Simulator The path makes no difference Heavy in the valley, light on the hill It takes two and a half times the height

Conservation of Momentum Simulator Impulse changes momentum They cancel on the inside The second equation is the restitution

Collision Simulator The wall carries the momentum off Every bounce multiplies it by e² Infinitely many bounces, and it stops

Circular Motion Simulator Constant speed and still accelerating There is no such force as centripetal force The flatter it lies, the faster it turns

Spring Pendulum Simulator Simple harmonic motion is a circle's shadow Velocity and acceleration are shadows too Energy only changes its form

Simple Pendulum Simulator A small swing is the same as a spring Height decides the speed In an accelerating train the vertical tilts

Planetary Orbit Simulator The Moon is falling too The nearer in, the faster The period is set by the size of the orbit Fast enough and it never returns