A Guide to 100 Musical Instruments Online

Optical Illusions

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Newton's Laws of Motion:

• 1st Law: Newton's First Law states that an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force. It may be seen as a statement about inertia, that objects will remain in their state of motion unless a force acts to change the motion.

  • NASA - Newton's 1st Law

  • Khan Academy - Newton's 1st Law of Motion

• 2nd Law: Newton's second law of motion pertains to the behavior of objects for which all existing forces are not balanced. The second law states that the acceleration of an object is dependent upon two variables - the net force acting upon the object and the mass of the object.

  • Khan Academy: Newton's 2nd Law of Motion

  • NASA: Newton's 2nd Law

• 3rd Law: A force is a push or a pull that acts upon an object as a results of its interaction with another object. ... These two forces are called action and reaction forces and are the subject of Newton's third law of motion. Formally stated, Newton's third law is: For every action, there is an equal and opposite reaction.

  • NASA: Newton's 3rd Law

  • Khan Academy: Newton's 3rd Law of Motion

Atoms

States of Matter: Solid, Liquid, Gas