Chapter 2 Motion along a line

Question 1

When describing where an object is located at we need to identify the _______ point, the distance, or the direction

Answer 1

Reference point

Question 2

The reference point is called the _______

Answer 2

Origin

Question 3

To describe the location of something we give its _________ from the place & the direction

Answer 3

Distance

Question 4

For graphing motion along a line the line of motion is the ___ axis & the origin is x=0 (or just 0) so the position of an object can be describe by its x-coordinate or how far from the origin point

Answer 4

X-axis

Question 5

Displacement

Answer 5

Is the change of position (final position- initial position) (symbol i delta X)

Question 6

Velocity

Answer 6

Is a quantity with magnitude & direction where the magnitude is the speed that the object is moving

Question 7

Velocity depends on both __________ & the time interval

Answer 7

Displacement

Question 8

Average Velocity

Answer 8

When a displacement (delta x) occurs over a time interval (delta t) the average velocity during that time interval is delta x divided over delta t

Question 9

Since delta t is always ________ the direction of the average velocity ( whether its -/+) depends on the __________

Answer 9

Displacement

Question 10

Average speed is the ______________

Answer 10

Total distance traveled divided by the time interval

Question 11

Instantaneous velocity

Answer 11

Is a quantity where the magnitude i the speed & the direction is the direction of motion

Question 12

A ________ shows the position of an object over a period of time so its a graphs that x vs t

Answer 12

Motion diagram

Question 13

For a graph that deals with displacement (delta X) on the x axis & time (delta T) on the y axis the velocity is the _________

Answer 13

Slope

Question 14

In a displacement vs t graph the tangent line is the _____________

Answer 14

Instantaneous velocity

Question 15

For a graph that is velocity vs time the _________ is the area under the graph (or the shape formed) ( the units are usually just meters_

Answer 15

Displacement

Question 16

When finding the displacement with graphs of changing velocity you would have to make smaller ________ for the certain area under the graph and then add up the area of all the shapes formed to get the total displacement

Answer 16

Shapes

Question 17

Acceleration

Answer 17

The rate of change of velocity (tells you how the velocity is changing)

Question 18

Average acceleration

Answer 18

Average acceleration during a time interval is the change velocity divided by the time interval (units is m/s²)

Question 19

To find ____________ acceleration have to calculate the average acceleration during a very short time interval

Answer 19

Instantaneous

Question 20

When acceleration & velocity is both in the same direction ( if both are in the positive x-direction or in the negative x-direction) the object is _________

Answer 20

Speeding up

Question 21

Only when acceleration & velocity are in the ______ direction when the object is slowing down

Answer 21

Opposite

Question 22

When velocity is positive & acceleration is negative the object is moving in the positive x-direction the object is ________

Answer 22

Slowing down

Question 23

When velocity is negative & acceleration is positive the object is moving in the positive x-direction the object is ________

Answer 23

Slowing down

Question 24

In a graph that is acceleration vs velocity the slope of the graph is the acceleration & the area under the graph is the __________

Answer 24

Velocity

Question 25

What are the 4 kinematic equations used when acceleration is constant?

Answer 25

1. delta V= a(delta)T
2. delta X = ½(V_f + V_i) (delta)T
3. delta X = V_i(delta)T + ½a(delta T)²
4. V_f² - V_i² = 2a(delta)X

Question 26

How do you calculate average velocity when acceleration is constant?

Answer 26

V = ½(V_f + V_i)

Question 27

In free fall its assumed that no other forces act on an object besides __________

Answer 27

Gravity

Question 28

An object in free fall has a constant downward acceleration called the ___________

Answer 28

Free-fall acceleration (gravity) (g is the symbol) (g=9.80m/s²)

Question 29

When dealing with vertical motion the y-axis is positive pointing upward & negative when pointing downward so in free fall the acceleration is what?

Answer 29

a = -g (-9.80m/s²)

Question 30

If an object is moving downward gravity ________ it up & if its moving upwards gravity slows it down

Answer 30

Speeds

Question 31

Explain why at the object peek height an object velocity is zero but acceleration isn’t zero?

Answer 31

When an object is at its peak height its velocity is zero but acceleration isn’t zero because when an object is thrown upwards its velocity is positive but when its falls back down its velocity is negative so acceleration can’t be zero because its needed to change the velocity

Question 32

When there no acceleration (when it says something travels at constant speed or constant velocity) what equation do you use?

Answer 32

delta X = vt (velocity x time)