Week 4-5: Newton's Law of Motion and Friction

Gravitational Force/Weight

Force exerted on a mass

Center of a gravity

Geometric center of an object

Elastic

Force exerted on elastic material

Compressive

Shortens

Tensile

Lengthens

Tension

A force that the strings, ropes, cables exerts on the object.

Normal Force

Force perpendicular to surface of contact

Friction

Force tangent to surface of contact

Net force

Vector sum of all force

Newton's 1st Law of Motion (Law of Inertia)

A body remains at rest will remain at rest and a body in motion will remain in motion at constant velocity in a straight line if no force acts on it.

Inertia

Ability of a body to resist any change in the state of motion of a body.

Newtons 2nd Law of Motion (Law of Acceleration)

Whenever an unbalanced force acts upon a body, an acceleration is produced which is directly proportional to the mass of the body.

Newton's 3rd Law of Motion (Law of Interaction)

For very action force, there is equal and opposite reaction force.

Mass

Quantity of matter in the body & same everywhere

Weight

Force of attraction of the earth on a body & varies ( depend on gravity )

Friction

- It is also a force.
- This force will go against the motion of two surface in motion when made contact with one another

Frictional Force

- An actual force that is exerted opposite the applied force.
-The reason why its hard to push and move an object on a surface

Coefficient of friction (µ )

- Ratio of the force of friction & the normal force .
- Measure the roughness of the two contacting surface.