You can create different types of bodies inside its physics world with different parameters like restitution, friction, velocity etc. attach them with different types of Joints like spring, rope, chain, pulley etc. Due to its native Physics engine the accuracy in solving is great.
One can visualize the motion with the numerous built in tools like tracers of points on body or Body ghosting, Graphs between different parameters( like KE, speed, velocity, momentum, etc), FBD of grouped and ungrouped objects, Camera tool ( to set frame of reference) etc.
It supports gravitational , electric, magnetic and buoyancy fields. One can even set variable fields ( time dependent ) and can easily change the fields as well using sliders.
One can create their own GUI elements in it like buttons , sliders , checkboxes , List , dialog etc. and even can write scriptable codes in them for different events in its in-built powerful scripting editing tool.
Nice interface and you can even add extra fields and script on buttons and sliders as well.
Songlio - Free musical guessing game: race friends to name that tune
Algodoo - Algodoo is a 2D simulator freeware product designed as a physics learning tool. It was originally created by Emil Emerfeldt as part of his master’s thesis in 2008. Read more about Algodoo.
Rock On! - A song pop adventure - music trivia awesomeness
Physion - Physics Simulation Sandbox
SongTrivia2.io - Songtrivia2.io is a browser and mobile blind test game that allows you to play in real time with your friends or against strangers. Several musical themes, difficulty and game modes are available to create lots of different musical quizzes.
Crayon Physics Deluxe - Crayon Physics Deluxe