newton’s first law. do bombs drop straight down from an airplane?
TRANSCRIPT
Newton’s First Law
Do bombs drop straight down from an airplane?
Objects in motion
Stay in Motion
Objects at rest
Stay at rest
“An object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force."
Is there an
unbalanced force at work here?
Stay in Motion
Inertia
Why seat belts were invented
A ball is launched straight up from a moving truck. Ignoring air resistance, where does the ball land relative to the truck?
The forward inertia of the ball is unaffected by its upward
motion.
Newton’s Second Law of Motion
Fnet=maF= force
m = mass
a= acceleration
Fnet=maFnet= force
m = mass
a= acceleration
Fnet=maFnet= force
m = mass
a= acceleration
Fnet=maFnet= force
m = mass
a= acceleration
Fnet=maFnet= force
m = mass
a= acceleration
What is net force?
Object accelerates
LARGER Force moving object forward
Smaller force resisting forward movement
What is net force?
Object maintains constant velocity
Force moving object forward
Equal force resisting motion
Newton’s Third law of Motion
Which team is applying more force to the
rope?
Neither- Both teams apply equal and opposite force.
•For every action force, there is a reaction force equal in strength and opposite in direction.
•For every action force, there is a reaction force equal in strength and opposite in direction.
Coanda effect
Coanda effect
The tendency of fluids to attach to a surface and follow it.
Do the forces on the ball tend to be balanced or unbalanced?
• Air moving along wing
• Deflected downwards when leaving wing
• Pushes craft up into the air
• Newton’s 3rd Law