Newton’s Laws Flashcards
What is a force?
A push or pull.
What are the two main types of forces?
1) Contact Forces
2) Long-Range Forces
What is the net force (ΣF)?
ΣF is the sum of the applied forces on an object:
ΣF = F1 + F2 + F3
What is the unit of force?
Newtons:
1 N = kg • m/s^2
What is inertia?
Inertia = measure of mass which exerts a resistance to motion
What is Newton’s First Law?
“An object at rest will remain at rest or an object in motion with constant velocity will remain in motion unless an external force acts on it.”
ΣF = 0
What does ΣF = 0 mean? What does it imply?
ΣF = 0 means that the object is either at rest or in constant motion where
v = constant and a = 0.
What is equilibrium?
When the ΣF = 0, the forces are balanced out and thus the object is at equilibrium.
What is the normal force?
The normal force (F_N) is:
1) perpendicular to the surface of contact
2) magnitude is the same as gravity if surface is horizontal
What is the relationship between force and acceleration?
ΣF ∝ a
the direction of acceleration is in the direction of the net force & is directly proportional
What is Newton’s Second Law?
“The net force applied to an object causes it to accelerate and in the direction of the force applied. The net force is equal to the mass times acceleration.”
ΣF = ma
What is momentum?
p = m•v
What is Newtons Second Law in terms of momentum?
ΣF = dp/dt
ΣF is the derivative of momentum over time
How can you find acceleration from force and mass?
Rearrange Newton’s 2nd Law:
a = ΣF / m
What is Newton’s Second Law as a vector equation?
ΣF = ma
=
ΣF_x = ma_x, ΣF_y = ma_y,
ΣF_z = ma_z,
