Unit 2: Forces Flashcards
Dynamics
the study of the causes of motion
newton (N)
the SI unit of force (1 N = 1 kg m/s2
system diagram
a simple sketch of all objects involves in a situation
free body diagram (FBD)
a simple drawing of an object showing all the forces that are acting on it
applied force
a force that results when one object makes contact with another and pushes or pulls on it
tension
a pulling force from a rope or string on an object that always points towards the rope or string
normal forces
a perpendicular force exerted by a surface: the normal always points away from the surface
friction
opposes the sliding of 2 surfaces across 1 another; friction acts opposite to the motion or attempted motion
force of gravity
force of attraction between any 2 objects
inertia
the property of matter that causes it to resist change in motion: inertia is direct proportional to the mass of the object
first law of motion
an object will remain at rest or continue to move at constant velocity when the net force on the object is zero
second law of motion
an object will accelerate in the direction of the net force: the magnitude of the acceleration is directed proportional to the magnitude of the net force and inversely proportional to the object’s mass
third law of motion
each action force has a reaction force that is equal in magnitude and opposite in direction
free fall
the motion of a falling object where the only force acting on the object is gravity
terminal speed
the maximum constant speed of a falling object
force field
a region of space surrounding on object that can exert a force an other objects that are placed within that region and are able to interact with that force
gravitational field strength
the force per unit mass acting on an object when placed in a gravitational field
static friction
a force of friction that prevents the sliding of 2 surfaces relative to 1 another
Kinetic friction
the force exerted on a moving object by a surface opposite to the direction of motion of the object
coefficient of friction
the ratio of the force friction to the normal force
coefficient of static friction
the ratio of the maximum force of static friction to the normal force
coefficient of Kinetic Friction
the ratio of kinetic friction to the normal force
