Mechanics I Flashcards
dynamics
the explanation of motion in terms of the forces that act on an object
force
a push or pull exerted by one object on another
newton’s first law
if the object is at rest or moving at constant velocity, it will continue this state of motion unless a force acts on the object causing acceleration “law of inertia”
mass
the quantitative measure of its inertia; how much matter is contained in an object
newton’s second law
net force=ma
newton’s third law: action-reaction pair
forces between interacting objects that are equal in magnitude but opposite in direction and act on opposite objects
weight
the gravitational force exerted on an object by the earth
Newton’s law of gravitation
mg=(GMm)/r^2, g=GM/r^2
static friction
when there’s no relative motion between the surfaces that are in contact (i.e. no sliding)
kinetic/sliding friction
when there is relative motion between the surfaces of contact (i.e. sliding)
normal force
the force that acts perpendicular to the surface that exerts it
coefficient of kinetic friction
an experimentally determined positive number with no units, the greater its value, the greater the force of kinetic friction
maximum coefficient of static friction
always greater than the coefficient of kinetic friction because static friction is capable of supplying any necessary force up to a certain maximum
inclined plane
system in which object is on a ramp and not a horizontal surface
incline angle
the angle the plane makes with the horizontal
