4.2 If a Net Force Acts on an Object, the Object Accelerates

What is the Friction force(f)?

-force resisting the sliding of an object across a surface

-parallel to the surface and opposite to the motion of an object

What is the Normal Force(n)?

-support force exerted upon an object that is in contact with another stable object

-perpendicular to the surface of contact

What is the Net External Force?

The vector sum of all external forces acting on an object

What are External Forces?

Forces exerted on an object by other objects

Describe the relationship between acceleration and mass with respect to Newton's 2nd Law

acceleration ↓ mass ↑

Why are mass and weight not the same thing?

mass is the same no matter where the object is

weight is affected by gravity

What is Gravitational Force(w)?

force of attraction between all masses in the universe

-> esp the attraction of Earth's mass for bodies near its surface

What are Internal Forces?

Forces exerted by one part of an object or system on another part

What is Newton's Second Law?

-if a net external force acts on an object, the object accelerates

What are the three essential features of Newton's 2nd Law?

1. A net force in a certain direction causes acceleration in that direction

2. The magnitude of acceleration caused by the net force depends on the object's mass

3. Only external forces acting on an object affect that object's acceleration

Does the net force or the individual force determine an object's acceleration?

net force

normal is another word for what?

perpendicular