Science Starter! Find your new seat!

Science Starter! Find your new seat!

Inertia

Tendency of an object to resist a change in motion.

Proportional to an object’s mass:Large mass High Inertia Difficult to move

Small mass Low Inertia Easy to move

Newton’s First Law of Motion

“Law of Inertia”

“Every object continues in a state of rest, or a state of motion in a straight line at constant speed, unless acted upon by an unbalanced force.”

Examples

Inertia Ring

Newton's Bottle

Egg Drop

Table Cloth Chaos

What role do SEATBELTS play in car safety?

Forces

Force: Push or pull (measured in Newtons [N])

Contact Forces: Forces that exist between surfaces that are touching

Field Forces: Forces that exist between surfaces that are not touching

FT

Fg

“Free-Body” Diagrams

v a = 0 m/s2

Example: A skydiver falling at constant velocity with an open parachute (ignore air resistance)

Free – Body Diagrams1. Object is drawn as a dot.2. Force Vectors (): labeled and pointing in direction of force.3. Arrows drawn starting from the dot, pointing away.* 4. Draw acceleration and velocity vectors next to diagram.

Example: Free-body diagram of a sky-diver with an open parachute

FT

Fg

v a = 0 m/s2

Examples

1. A ball hangs motionlessly from a

cord.

2. A ball rests in the palm of a hand.