Presentation on theme: "INERTIA An object will remain at rest or in constant motion unless acted upon by an unbalanced force. “THE OLD TABLECLOTH TRICK”"— Presentation transcript:
INERTIA An object will remain at rest or in constant motion unless acted upon by an unbalanced force. “THE OLD TABLECLOTH TRICK”
WHICH HAS MORE MASS?
LESS MASS = LESS INERTIA The skier does not have a lot of mass therefore has LESS inertia; & is easier to stop MORE MASS = MORE INERTIA The car has MORE MASS therefore has A LOT OF INERTIA; & is harder to stop
Finger applies a force to a card causing it to move Penny STAYS at rest (over the cup) due to inertia Gravity causes the penny to fall into cup
What happened to the spinning hardboiled egg when you tapped it? The egg stopped spinning Why? The egg is a solid unit and the finger applied enough force to change the inertia What happened to the spinning raw egg when you tapped it & let go? The egg continued to spin Why? The liquids inside the egg were in motion & wanted to stay in motion due to inertia
Which cup was easier to keep standing? The cup (more massive one) because it has more inertia The empty cup was harder to keep standing because it has less mass therefore less inertia
Vectors- arrows that show the direction & strength (magnitude) of a force Longer Arrow = Stronger Force Shorter Arrow = Weaker Force Forces measured in Newtons (N)
Cancel each other out so net force = O Results in NO MOTION or NO CHANGE in motion
Forces that don’t cancel & the object moves in the direction of the stronger force. DIFFERENT directions, SUBTRACT the forces SAME direction, ADD the forces.
An object acted on by an unbalanced force accelerated in the direction of the force
Force= mass x acceleration Mass (kg or grams) Acceleration (m/s 2 ) 1 Newton= force needed to move 1 kg 1 m/s 2
More Mass = More Gravity Earth has more gravity than Moon b/c Earth is more massive More Distance = Less gravity Acceleration due to Gravity = 9.8 m/s 2