## Newton's Laws of Motion

Force
When forces are unbalanced, objects accelerate. But what factors affect the amount of acceleration? This Interactive allows learners to investigate a variety of factors that affect the acceleration of a box pushed across a surface, The amount of applied force, the mass, and the friction can be altered. A plot of velocity as a function of time can be used to determine the acceleration.

Balanced vs. Unbalanced Forces
The Balanced vs. Unbalanced Force Interactive is a skill-building exercise that challenges students to associate representations of an object's motion with the presence of balanced or unbalanced forces. Several representations are used including dot diagrams, position-time graphs, velocity-time graphs, position-time tables, and velocity-time tables. The Interactive offers three different levels of difficulty and includes built-in progress-tracking for each level. Every question is accompanied by a Help page that includes question-specific help relevant to the question.The Interactive makes a great classroom activity for the transition from Newton's first law to Newton's second law.

Free-Body Diagrams
The Free-Body Diagrams Interactive is a skill-building tool that presents users with 12 physical situations for which they must construct free-body diagrams. On-screen buttons are used to select up-down-right-left force types. Force arrows can be clicked/tapped to toggle the magnitude of the force. Feedback is immediate; opportunities to correct answers are endless. Built-in score-keeping makes this Interactive a perfect candidate for a classroom activity.

Rocket Sledder
Created by our friends at Nerd Island Studios, this Interactive illustrates the effect of friction, air resistance, and applied force upon a sledder. The speed, acceleration, and force values are displayed as the sled moves. Learners can vary the mass of the sledder and the size of the parachute that is attached to it.

Which One Doesn't Belong?
Play the classic game Which One Doesn't Belong? and identify the one representaton of motion that isn't like the others. The emphasis of this skill-building activity is to relate the forces acting upon an object to the various ways of representing the subsequent motion. There are three different levels of difficulty and built-in progress-tracking for each level. Every question is accompanied by a Help page with question-specific help relevant to the question.The Interactive makes a great classroom activity for building concepts related to Newton's first and second laws.

Skydiving
Created by our friends at Nerd Island Studios, this Interactive allows the learner to explore the motion of an object falling under the influence of air resistance. Force arrows and values are shown as the object falls. A speedometer displays the speed of the object; the height is listed as well. The mass of the falling object and the size of its parachute can be varied. Enjoy the Skydiving Interactive without the fear of falling.

You might have wondered why you get that queasy feeling in an elevator as you start up and slow down. The phenomenon is explained by some simple physics. This Interactive allows a learner to explore the physics behind the sensations of weightlessness and weightiness ... and you won't get sick in the process.
Everyone is fascinated by pulleys. In this Interactive, learners will attach two objects together by a string and stretch the string over a pulley. Both an Atwood's machine and a modified Atwood's machine can be created and studies. Change the amount of mass on either object, introduce friction forces, and measure distance and time in order to calculate the acceleration.