Newtons First Law
What is Newton's first name?
Isaac Newton
What is the equation for Newton's second law?
Fnet = ma
What is gravitational force?
An attractive (pulling) force between any 2 objects with mass
What properties do forces have that allow us to classify them as vectors?
Direction and Magnitude
What is a force?
A push or pull on an object
If the net force of an object is ___, then that object will have zero acceleration.
If the net force on an object is zero, then that object will have zero acceleration.
Objects will _____ in the direction of the net force
Objects will accelerate in the direction of the net force.
What is normal force?
A force that opposes gravity. Acts perpendicular to an object that is lying on a surface
An object can only accelerate if a net force acts on it. True or False?
True!
What is a contact force?
A force that acts when two objects are TOUCHING
f an elephant were chasing you, its enormous mass would be most threatening. But if you zigzagged, its mass would be to your advantage. Why?
The elephant has a huge amount of inertia! This makes it very hard to turn
Larger _____ require greater ___ _____ to accelerate the same amount.
Larger masses require greater net force to accelerate the same amount.
What is tensional force?
A pulling force! Typically through a rope, cable, string, etc.
Imagine you are standing in a bus that suddenly turns sharply. Why do you feel like you're being pushed sideways, even though nothing is pushing you directly?
Inertia!
What is field force?
A force that acts at a DISTANCE
An object at ___ will stay at ___, or in motion, remains in motion at a _____ constant velocity unless acted on by a net _____ force.
An object at rest remains at rest, or if in motion, remains in motion at a constant velocity unless acted on by a net external force.
Acceleration of an object is directly proportional to the ____________________ acting on it, and inversely proportional to the _________________ of the object.
net force; mass
What is friction?
A boy is pulling a wagon to the right with a force of 6 N. At the same time, another boy is pulling the wagon to the left with a force of 15N.
What is the net force on the wagon?
9 N to the left
What is inertia?
The tendency of an object to NOT accelerate/change speed
What is Newton's First Law?
Hint: Law of I-
The Law of Inertia
Suppose a cart is being moved by a certain net force. If a box is dumped into the cart, so its mass is doubled, by how much does the acceleration change?
the acceleration will be cut in half!
Acceleration is inversely proportional to mass
What is air resistance?
A force that directly opposes motion of an object that is moving through the air
What is the acceleration of the 3 kg box that has 25 N of force applied to the right and 55 N left?
10 m/s/s to the left!
What is equilibrium?
the state in which the net force on an object is ZERO