Unit 6

Today in class we learned about Newtons 2nd law, and motion. This unit will mostly be covering motion and forces, and more force diagrams. Newtons 2nd law is the Law of Motion, it  basically says that the acceleration of an object is directly proportional to the net force acting on that object, and inversely proportional to its mass. This can be put into an equation which is F = ma. F is the net force (all forces acting on the object added together), m is the bass and a is the acceleration of the object.

A force diagram is just a diagram that shows all the forces acting upon a single object. When drawing these you need to make sure you only draw forces and not things just sliding due to lack of friction. If the surface of what your object is sliding on has no friction or has friction it could effect your force diagram. Make sure to know if there is friction or not!!

An example of Newtons 2nd law is...

An elevator is moving up at a constant velocity of 2.5m/s, The man has a mass of 85kg.
Question:
What force does the floor exert on the man?
In order to find this out we will need to use the equation N=mg this translates to numbers as 85kg(9.8m/s^2)=833N
We now know that the elevator floor is putting a force of 833N on the man.

The reason I scorpion instead of sliding down easily and painlessly is because of friction. In this picture you can clearly see friction stopping me and thats kind of why I face plant. Twas very sucky.