concept physics chapter 4 in notes and 2 in text – Flashcards
Unlock all answers in this set
Unlock answersquestion
When we describe the motion of one object with respect to another, we say that....
answer
the object is moving relative to the other object
question
an object is _____ if its position relative to a fixed point is ______.
answer
moving, changing
question
A driver is going 20 kilometers per hour down the street. What is the driver's speed relative to?
answer
Air and the center of the galaxy
question
What is a measure of how fast something is moving?
answer
speed
question
what is the equations and how do you calculate speed?
answer
speed= distance/ time
question
what is speed and any instant?
answer
instantaneous speed
question
what on a car shows instantaneous speed?
answer
the speedometer
question
how is average speed calculated?
answer
average speed= total distance covered/ time interval
question
velocity is a vector of what?
answer
quantity
question
Either the ____ or the _____ is changing (or both are), when the velocity is changing.
answer
speed, direction
question
What is the rate at which velocity is changing?
answer
acceleration
question
how is acceleration calculated?
answer
acceleration= change of velocity/ time interval
question
acceleration is also a vector of _____.
answer
quantity
question
An object moving under the influence of the gravitational force only is said to be in _____.
answer
free fall
question
What is time that has passed since the start of the fall?
answer
elapsed time
question
What is an appropriate value of the acceleration of an object in free fall?
answer
10 m/s^2
question
what is used to represent acceleration due to gravity?
answer
g
question
what is an accurate value of acceleration of an object in free fall?
answer
9.8 m/s^2
question
what is used for both speed and velocity in the equation for instantaneousness speed?
answer
v
question
what is the instantaneous speed of an object that is at its highest point when it is thrown straight up in the air?
answer
zero
question
when an object is thrown straight up into the air, what is its acceleration when it is moving upward?
answer
10 meters per second squared down
question
For each second of free fall, an object falls a greater distance than it did in the ____ _____.
answer
previous second
question
At the end of time t, an object in free fall has fallen a distance equal to ___.
answer
distance
question
What are the two equations used to calculate velocity and distance for a freely falling object?
answer
1. v- gt
2. v=1/2gt^2
question
explain why a dropped coin reaches the ground before a feather.
answer
because air resistance less noticeably affects the motion of more compact objects.
question
explain what would happen if a coin and a feather were dropped at the same time in a vacuum.
answer
they would hit the ground at the same time because they would fall with the same acceleration because there is not air resistance in the vacuum
question
If air resistance is negligible, a falling object can be considered____ _____.
answer
freely falling
question
what is the word for how fast something freely falls from rest after an elapsed time?
answer
speed
question
what is the equation for speed and velocity?
answer
v=gt
question
what is the word for how far an object has fallen?
answer
distance
question
what is the equation for distance?
answer
d= 1/2 gt^2
question
what is the word for the rate at which velocity changes?
answer
acceleration
question
what is the object or point from which movement is determined?
answer
frame of reference
question
What is the most common frame of reference?
answer
Earth
question
What is speed in a given direction?
answer
velocity
question
What is the total distance divided by total time?
answer
average speed
question
What is the rate of change in velocity?
answer
acceleration
question
What is the change in position relative to a frame of reference?
answer
motion
question
what is any change over time?
answer
rate
question
What is the rate of motion at any given instant?
answer
instantaneous speed
question
What is the motion under the influence of gravity over?
answer
free fall
question
When we describe the motion of one object with respect for another, we say that the object is moving _____to the other object
answer
relative
question
What is the total distance covered by time?
answer
average speed
question
What is the difference between speed and velocity?
answer
Speed is a description of how fast an object moves; velocity is how fast and in what direction it moves
question
What is the rate at which the velocity is changing?
answer
acceleration
question
What happens when acceleration is in the direction of velocity?
answer
you speed up
question
What happens when acceleration is against velocity?
answer
you slow down
question
What happens when acceleration is at an angle of velocity?
answer
you change direction
question
An object moving under the influence of the gravitational force only is said to be in ______.
answer
free fall
question
The ___ _____ is the time that has elapsed, or passed, since the beginning of any motion, in this cause the fall.
answer
elapsed time
question
A vehicle undergoes acceleration when what three things happen?
answer
it gains speed, decreases speed, and changes direction.
question
The slope of a speed-versus-time graph represents what?
answer
acceleration
question
What and what are actually entirely different concepts?
answer
speed and acceleration
