Science Exam 2 Flashcards
compound motion
two forces acting on the same object
Newton’s first law of motion
law of inertia
what does the law of inertia say
an object in motion stays in motion unless acted upon by an outside force. Additionally, an object at rest stays at rest
in the law of inertia, what direct does an object travel in motion
straight line travel
what example can be used to demonstrate Newton’s first law of motion
a human standing on a bus- the body wants to stay where it is but it can’t because the bus is moving so the body will shift around
Newton’s second law of motion
law of acceleration
what does Newton’s second law say?
forces cause acceleration (change in motion)
more force= (more, less) acceleration
more mass = (more, less) acceleration
more force= MORE acceleration
more mass = LESS acceleration
are weight and mass the same thing?
no, it’s a difference between weight and gravity
mass compared to weight (definitions)
mass is the measure of inertia/amount of matter, whereas weight is the force of gravity acting on the mass
Newton’s third law of motion
Force
what does Newton’s third law of motion say?
for every action there is an equal and opposite reaction
where do forces come from?
from objects or objects that exert force
what example can be used to demonstrate Newton’s third law of motion?
an astronaut pushes against a satellite in space and both of them move in opposite directions from one another
momentum
includes effects of both motion (velocity) and inertia (mass)
t/f: anything with motion has to have other factors affecting it
true
law of conservation of momentum
the system has to stay equal/ the total momentum of a group of interacting objects remains the same in the absence of external forces
when centripetal force stops, motion continues in what direction
a straight line
simple machine 1 & example
wheel and axel, potter’s wheel, windmill
simple machine 2 & example
pulley, flagpole, zipline, ski slope
simple machine 3
lever
example of first class lever
hammer, see-saw
example of second class lever
wheelbarrow, stapler
example of third class lever
baseball bat, raking leaves
simple machine 4 & example
wedge, zippers, axes, shovels, doorstops
simple machine 5 & example
screw, bolt, worm gear, drill bit
simple machine 6 & example
inclined plane, going down a slide, skiing
what is thermodynamics
science of the relationship of heat, work, temp and energy
zeroth law of thermodynamics, and example
temp exists and is measurable, temperature gauge
first law of thermodynamics and example
energy can never be created or destroyed, it can only be converted. Ex. metabolism
second law of thermodynamics, and example
entropy (chaos level) of an isolated system never decreases, ex. ice cream goes from cold to hot, coffee goes from hot to cold
third law of thermodynamics, and example
the lower the temp, the less energy/chaos, ex. MRI machines
temperature will always reach
equilibrium (hot soup, cold ice cream)
temperature is the measurement of how fast _____ are moving
molecules
Absolute zero is when energy is completely …
stopped
is is possible to reach absolute zero
no
gravity provides _____ force
centripetal
all objects that have ____ will experience _____ force
mass, centripetal
centripetal force is
a force that pulls an object towards the center of a circle, keeping it moving in a circular path
energy
the ability/capacity to do work; work waiting to happen
energy is a (scalar, vector) quantity
scalar
work is a (scalar, vector) quantity
scalar
power refers to
the rate at which work gets done
potential energy is based on the
position of the physical matter
potential energy is energy that is there because of
the position of the object/ the stored energy
kinetic energy is
energy by virtue of motion
kinetic energy relationship to faster moving vehicles
it explains why a faster moving collision does such damage versus a slower moving collision, because there is more energy being created due to the velocity of the object
if an object was spun in a circle and then was let go of, what direction would it travel
in a straight line
Henry Cavendish is thought to have done what in the world of physics?
he was able to measure the earth’s density and calculate the gravitational constant, essentially allowing him to “weigh” the earth
work is accomplished when…
an object is “moved”/force is applied and the force is successful in doing its job
what are some different forms of energy
electrical, radiant, chemical, nuclear, mechanical
work-energy theorem
the net work done on an object is equal to the change in its kinetic energy
what is a mechanical advantage
using a mechanical system to make something easier. Example, a wheelchair ramp to get someone disabled up steps. A pulley to lift something heavy up high
energy source: ge
geothermal
energy source: hy
hydrogen
energy source: wi
wind
energy source: so
solar
energy source: nu
nuclear
energy source: hy el
hydroelectric
energy source: ff
fossil fuels
work is
force done to an object that makes it change position over a distance
force is a (scalar, vector)?
vector
groups of resistance (what do we need to overcome resistant wise when doing work?)
inertia, gravity, friction, shape
work against resistance results in increases in …
KE, PE, temperature, or a combination of the three
