Newtons Laws

A little intro with a bit of text

 

1. Newtons 1st Law

Newton's First Law states that a body will remain stationary or move at a constant velocity unless acted upon by a resultant force. I also show you a few examples including why the reaction/normal/contact force is not equal to the weight. 

 

2. Newtons 2nd Law

F=ma is good but not always correct. A better definition of Newton's 2nd Law is to say that the force is directly proportional to the rate of change of momentum and acts in the same direction (this last part is really important). This covers examples where the mass or acceleration may not remain constant.

 

3. Newtons 3rd Law

Newton's 3rd Law: If object A exerts a force on object B, then object B exerts an equal and opposite force of the same type on object A (this is better than 'every action has an equal and opposite reaction'). This sounds simple but is what many people find difficult identifying in questions.

 

Newtons 2nd Law and F=ma

Video text goes in here, with two lines at the end.