Physical Science Flashcards
equation for Work (W)
W = F x d (displacement)
power is…
the rate at which work is done
examples of simple machines
plane, lever, wheel and axle, and pulley
kinetic energy
energy of motion; measured in joules
changes in kinetic energy occur when a force does work on an object and what is altered
speed
potential energy is
stored
lifting an object increases its
gravitational potential energy
compressing or expanding of an elastic or spring is…
elastic potential energy
power equation
power = work/time
the purpose of a simple machine is…
to decrease the amount of force required to do the same amount of work by increasing the distance
an inclined plane
ramp; like getting on box onto a moving truck
a wedge
a movable inclined plane; helps split or lift objects; knives, axes, doorstops, plows
screw
a wedge or inclined plane wrapped around a shaft or post. screws into objects. less force than a hammer/nail.
lever
easier to lift something; like a seesaw, apply force to one side and the other side moves (seesaw, wheelbarrel)
wheel and axle
faucet, bike tire
pulley
a wheel with a rope wrapped around it. more ropes makes things easier to pull
the amount of energy in a system
is conserved. it stays the same; it can change forms, be transferred between objects
displacement
when something changes location from one place to another
acceleration
change in velocity of an object
friction
is equal and opposite to our force
the first property of friction
if the body does not move when horizontal force F is applied, then the static frictional force is equal and opposite
electrical charge is transferred in 3 ways
conduction, induction, and friction
electrical charge conduction
takes places between two conductive materials. There must be a point of contact between the two materials, and a potential difference
induction of electrical charge
requires conductive materials, occurs due to on ematerial encountering a varying magnetic field
