Newton

speed

how fast something moves

velocity

how fast something moves and the direction it moves

inertia

the property of things to resist changes in motion

free fall

motion under the influence of gravity only

net force

the vector sum of forces that act on an object

force

a push or pull

acceleration

the rate at which velocity changes

a car maintains a constant velocity of 100 km/hr for 10 seconds. during this interval it's acceleration is:

zero

equilibrium occurs when

- all the forces acting on an object are balanced- the sum of the +x forces on an object equals the sum of the -x forces- the sum of the upward forces equals the sum of the downward forces- the net force on the object is zero(all of the above)

suppose you are in a car that is going around a curve. the speedometer reads a constant 30 mph. which of the following is NOT true?

your velocity is constant

a 10 n force and a 30 n force act on an object in opposite directions. what is the net force on the object?

20 n(30-10)

twelve seconds after starting from rest, an object falling freely will have a speed of

120 m/s(12 x 10)

the quantity of matter in an object

mass

the resistive force that opposes the motion or attempted motion of an object

friction

the SI unit of force

newton

a quantity that has both magnitude and direction

vector quantity

a quantity that has magnitude but not direction

scalar quantity

motion under the influence of gravitational pull only

free fall

the quantity of space an object occupies

volume

the speed at which air resistance balances the weight of an object

terminal speed

the force due to gravity on an object

weight

the combination of two or more vectors

resolution

a tennis ball and a solid steel ball, the same size, are dropped at the same time. in the absence of air resistance, which ball has a greater acceleration?

they have the same acceleration

a tennis ball and a solid steel ball, the same size are dropped at the same time. which ball has the greater magnitude of force acting on it?

the steel ball

whenever there is an action force, there must be a reaction force which

is exactly equal in magnitude

force always occur

in pairs

a baseball player bats a ball with a force of 1000 n. the reaction force that the ball exerts against the bat is

1000 n

a player catches a ball. consider the action force to be the impact of the ball against the player's glove. the reaction to this force is

the force the glove exerts on the ball

when an object reaches terminal velocity it's acceleration is

0 m/s

the product of the force and the distance moved by the force

work

the energy something possesses because of its position

potential energy

the rate at which energy is expended

efficiency

the product of the force acting on an object and the time during which it acts

impulse

energy in motion

kinetic energy

a device that increases or decreases a force or changes the direction of a force.

machine

the difference between impulse and impact force involves the

time the force acts

when you jump from an elevated position you usually bend your knees upon reaching the ground. by doing this, you make the time of the impact 10 times as great as for the stiff-legged landing. in this way, the average force your body experiences is

about 1/10 as great

padded dashboards in cars are safer in an accident than nonpadded ones because an occupant hitting the dash has

increased time of impact

if an object has kinetic energy, then it also must have

momentum

an object that has kinetic energy must be

moving

a hydraulic press, like a pulley, is capable of increasing energy.

always false

the curved path followed by a projectile under the influence of gravity

parabola

any object that moves through the air or through space under the influence of gravity

projectile

a projectile or small celestial body that orbits a larger celestial body

satellite

the oval path followed by a satellite

ellipse

inside a freely falling elevator, there would be no

apparent weight for you

the earth's gravitational field extends

both inside and outside the earth and throughout the entire universe

the horizontal component of a projectile's velocity is independent of

the vertical component of its velocity

a bullet fired horizontally from a rifle begins to fall

as soon as it leaves the barrel

different forms of an atom that contains the same number of protons but different number of neutrons

isotopes

a material in which atoms of different elements are chemically bonded to one another

compound

the smallest particle of an element that has all the element's chemical properties

atom

a substance whose components are mixed together without combining chemically

mixture

a pure substance consisting of only one kind of atom

element

a group of atoms held together by sharing of electrons

molecule

the number that designates the identity of an element, the number of protons in the nucleus of an atom

atomic number

any device that measures atmospheric pressure

barometer

the ratio of force over the area which the force is applied

pressure

the net upward force that a fluid exerts on an immersed object

buoyant force

what makes an element distinct

the number of protons

the weight of matter comes mostly from its

nucleons

the volume of matter comes mostly from its

electrons

if the mass of an object doubled while its volume stays the same, its density would

double

a dam is thicker at the bottom than at the top partly because

water pressure is greater with increasing depth

a lobster crawls onto a bathroom scale submerged at the bottom of the ocean. compared to the weight above the surface, the lobster will have an apparent weight under the water that is

less

the flight of a blimp best illustrates

the principle of Archimedes.

a balloon is buoyed up with a force equal to the

weight of air it displaces

the radiation emitted by the earth to outer space

terrestrial

the energy that flows from a substance of higher temperature to a substance of lower temperature

heat

the rate of heat loss is proportional to the temperature difference between the object and it's surroundings

newton's law of cooling

transfer of heat by molecular collisions

conduction

the lowest possible temperature that a substance may have

absolute zero

transfer of heat by currents within the fluid

convection

a measure of the average translational kinetic energy per molecule in a substance

temperature

the change of phase from gas to liquid

condensation

a process wherein no heat enters or leaves a system

adiabatic

the change of phase from liquid to gas

evaporation

the study of heat and its transformation to different forms of energy

thermodynamics

rapid evaporation throughout the liquid

boiling

the change of phase from solid to gas, skipping the liquid phase

sublimation

a measure of the disorder of a system

entropy

heat energy travels from an object with a high

temperature to an object with a lower temperature

a substance that heats up relatively quickly has a

low specific heat

the moderate temperatures of islands throughout the world has much to do with water's

high specific heat

metals are both good heat conductors and good electrical conductors because of

looseness of outer electrons in metal atoms

energy transfer by convection is primarily restricted to

fluids

both black and white road surfaces absorb sunlight. at the end of a sunny day, the warmer road surface would be

the black surface

both black and white surfaces radiate energy. at the end of a starry night, the warmer road surface will be

the white surface

evaporation is a cooling process because

the more energetic molecules are able to escape the liquid

steam burns are more damaging than burns caused by boiling water because steam

gives up additional energy when it condenses
has more energy per kilogram than boiling water
(both a + b)

which involves the larger number of calories?

the condensation of 1 gram of steam at 100 degrees c to water at 100 degrees c

systems that are left alone, tend to move toward a state of

more entropy

an adiabatic process is characterized by the absence of

heat exchange

when a volume of air is compressed and no heat enters or leaves, the air temperature will

increase