Physics free fall
what is the acceleration of an object in free fall at the surface of the earth
-9.8m/s2
air resistance
a force that opposes the motion of a body through the air and that is the result of collisions between the moving body and the molecules that compose air
mass
a measure of the inertia of an object or a measure of the quantity of matter in an object
vacuum
a region where there is no air or any other gaseous quantity and therefore absolutely no air resistance
what does the slope of a velocity time graph represent. what units
acceleration, m/s2
fluid
anything that flows in particular any liquid or gas
law of falling bodies
as first stated by galileo in a vacuum and only in a vacuum all bodies fall with the same acceleration
what is true about freely falling objects that is true
fall with same acceleration, net force acting on them is weight, their weight-to-mass ratios are always the same, their acceleration is g, the acceleration due to gravity
for a freely falling object how does the distance it falls per second change with each second
for each second of free fall an object falls a greater distance than it did in the previous second
an object dropped in air that experiences no air resistance is said to be in
free fall
when an object is in free fall, the only force acting on the object is
gravity
how does air resistance affect falling objects
slows the motion of things with large surface areas
what factors affect the air resistance force on an object
speed and area
what factors affects the amount of air resistance experienced by an object
surface and speed of object through air
terminal velocity
terminal speed together with the direction of motion
free fall acceleration, g
the acceleration of an object when gravity is the only force acting on it
weight
the downward force on an object due to the gravitational pull of earth on the object
fluid resistance or drag
the force exerted by any fluid on an object moving through the fluid. it depends on the nature of the of the fluid, the speed of the object through the fluid, and the area of the object in the direction of tis motion through the fluid
why do all free falling objects fall with the same acceleration
the net force on an object is only its weight and the ratio of weight to mass is the same for all objects
what is the relationship between velocity and acceleration
the rate what which the velocity changes
a 1kg rock and a 10kg small boulder are dropped from the back of a truck at the same time. which will hit the ground first
the same time
what is terminal speed
the speed at which the acceleration of a falling object is zero because friction balances the weight
elapsed time
the time that has passed since the beginning of an event
free fall
the vertical upward or downward motion of an object when the only vertical force acting on it is gravity
weight-to-mass ratio
the weight of an object divded by the mass of the object. it always has the same value at the same location regardless of the object
identify the conditions needed for a feather and a coin to fall at the same rate
they need to be in a vacuum
what describes the forces that are in balance when an object reaches its terminal speed
weight and air resistence
