Physics Final Exam

speed

a scalar quantity that does not have a direction

velocity

a scalar quantity that includes speed and direction

acceleration

the change in velocity per unit of time

instantaneous speed

the speed at that instant

-9.8 m/s^2

when objects are free falling what is the acceleration?

straight down

what is the direction of acceleration of falling objects?

speed up

do objects in free fall speed up or slow down as they fall?

no because the speed is always changing because of gravity

is an object that is free falling have a constant speed?

zero

at the top of an objects path, the speed at the top is ____?

velocity

what is the slope of a displacement time graph?

acceleration

what is the slop of a velocity-time graph?

displacement

what is the area under a velocity-time graph?

velocity

what is the area under an acceleration time graph?

independent

vertical and horizontal velocities are completely ______ of each other?

45 degrees

the maximum range when an object is projected at is ___?

same; slow; speed

if an object is projected at an angle the horizontal velocity is the __for the entire trip and the vertical velocity will __as it goes up and __up as it goes down.

inertia

an object will remain its present state of motion unless an outside force acts on it.

mass

the measure of inertia

newtons 2nd law

force causes acceleration

pairs

forces always come in ___?

newtons 3rd law

for every action there is an opposite and equal reaction

force

objects of different mass will have different weights so there is a different ___ acting on each.

more

if you are in an elevator accelerating upward you would appear to weigh ___?

less

if you are in an elevator accelerating downward you would appear to weigh ___?

the same

if you are in an elevator moving at a constant speed you would appear to weigh ___?

weightless

if you are in an elevator at free fall you would appear to be ___?

frictional force

always in the opposite direction of the motion

normal force

always perpendicular to the surface

linear speed

the distance traveled per unit of time

angular speed

the angle traveled through per unit of time

tangential (linear) speed

velocity of an object in circular motion is always tangent to the circular path

centripetal force

to maintain circular motion there must be a ___ directed toward the center of the path.

speed; velocity

constant _ is possible during circular motion but constant _ is not possible because the direction is constantly changing which means the object is accelerating.

universal law of gravitation

there is an attractive force between all objects proportional to the product of their masses and inversely proportional to the square of the distance between them. This means as the masses increase the force increase by the same factor and if the distance increases the force will decrease by the square of that factor of distance increase.

joule

what are the units for work and energy?

work

the force on an object times its displacement

watts

what is power measured in?

power

the work done per unit of time

gravitational potential energy

the energy an object has due to its distance above the ground

elastic potential energy

the energy due to the compression or elongation of a spring

kinetic energy

the energy due to the objects speed

kinetic energy

gravitational potential energy can be converted to ___ and vice versa.

work

___ can be done to produce a change in kinetic energy.

momentum

mass times velocity

change in momentum

mass times the change in velocity

momentum

____ is always conserved in collisions.

elastic collision

a collision in which both the momentum and kinetic energy is conserved like billiard balls

perfectly inelastic collision

collision in which momentum is conserved but kinetic energy is not and the objects stick and move together after the collision

torque

force times the radius of the lever arm

perpendicular; force

to get maximum torque increase the radius of the lever arm, apply force _ to the lever arm, and increase the _?

wave

carries energy from one place to another

period

time to complete one cycle

wavelength

the distance from one wave crest to the other

frequency

the amount of wave fronts or beats per second

amplitude

height of the wave

the doppler effect

apparent change in frequency due to the speed or source of the observer

medium

sound waves require a __ to travel through

frequency

beats can be heard when two tuning forks have almost the same __ and are sounded together