CP) Ch 6

acceleration formula

a=f/m

Cause of acceleration

an unbalanced net force

potential energy (PE)

stored energy or rest (ability to move but not currently moving)

kinetic energy (KE)

movement

velocity

speed in a given direction

net force

total force working together

~

directly proportional to

to increase the acceleration

increase the net force

relationship between acceleration and net force

proportional

Newton's Second Law

F=ma

increase in mass affect on acceleration

decrease in acceleration

relationship between mass and acceleration

inversely proportional

inversely

two values change in opposite directions

unit of force (F)

N (Newton)

unit of mass (M)

kg (kilogram)

unit of acceleration (A)

m/s2 (meter per second squared)

if net force doubles

acceleration doubles

if mass doubles

acceleration will be halved

if both mass and net force doubles

acceleration will be unchanged

the direction of friction

opposite the direction of force

cause of friction

irregularities in two surfaces

liquid and gases called

fluids (cause they flow)

fluid friction

occurs when a solid object moves through a fluid

air resistance

Fluid friction acting on an object moving through the air

Free body disgram

a diagram showing all the forces acting on an object

friction relies on

movement

pressure between 2 surfaces/gravity/the surfaces irregularities

force of friction

if there is more contact area the pressure

lessens

pressure

amount of force per unit of area

pressure formula

P=F/A

Unit of pressure

Pascal (Pa)

ratio of weight to mass is the same for all objects

if air resistance doesn't apply

if air resistance is very small

ratio of weight to mass is approximately same for all objects

relationship between force and mass

directly proportional

all free falling objects undergo the same acceleration on

the same place on earth

air resistance depends on

the objects speed and area

the force due to air resistance diminishes

the net force acting no the falling objects

if gravity and air resistance act on a falling object is not

free fall

more speed

more air resistance

air resistance formula

air resistance ~ speed x frontal area

terminal speed

the speed at which the acceleration of a falling object is zero because friction balances the weight

terminal velocity

terminal speed together with the direction of motion

constant velocity

zero acceleration

terminal velocity is reached when air resistance equals

weight

factors that determine air resistance on an object

force, mass, speed, frontal area

an object will accelerate when

it is pushed or pulled with a net force

when a net force acts on an object, it acceleration depends on the object's

mass

double the net force and increase the mass by four the acceleration would be

half

friction force occurs in

solids sliding over one another, fluids and air

when you stand on one foot instead of two, the pressure you exert on the ground is

twice as much as before

The reason a 20-kg rock falls no faster than a 10-kg rock in free fall is that

the force/mass is the same

why does a heavier object have a a greater terminal velocity even while using the same parachute

it has to fall faster for air resistance to match its weight