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kinetmatics

modern name for mathematical description of motion, without regard of causes

the right of the X-axis

which sides of the coordinate system are positive in motion?

position graph

position-vs-time graph (other name and definition)

a graph is an_

abstract representation of motion

-In horizontal plane, the motion can be from right lo left

what are the motions that can be done in 1-dimension movement in horizontal plane? in vertical?

what is the relation between speed and velocity?

speed is the magnitude of the velocity vector and is always positive

the faster the speed=the steeper the slope

how the speed relates in a position graph or position-vs-time graph?

how determine slope of position graph?

rise/run= change in X/ change in t

velocity at that point in the motion

The slope of an object's position-versus-time graph is the object's _

by reading the graph at that instant of time time

How the information about motion can be obtained from a position-vs-time graphs in the following case: Determine an object's position at time t_

by finding the slope of the position graph at that point. Steeper slopes correspond to faster speeds

How the information about motion can be obtained from a position-vs-time graphs in the following case: Determine the object's velocity at time t

intervals

the slope is a ratio of_not a ratio of_

physical meaningful slope

the slope obtained by measuring the rise and run using the scales along the axes

what is the problem of the velocity-vs-time graph?

it does not tell us the start position in reference to the origin

what is the acceleration formula?

ax= change in velocity (v)/ change in temperature

0 at all time because velocity is not changing

when the velocity is constant, what is the value of acceleration? why?

the value of the instantaneous velocity Vx at that point

the slope of a line tangent to to x(t) curve at any point equals _

How acceleration relates with velocity?

the acceleration bears the same relationship to velocity as velocity bears to Change in X (position)

How the MD (Motion Detector) of our experiment works?

the MD emits sound pulses several times a Second

Where is the origin located when using the MD?

The position is measured from the motion detector, so the motion detector is the origin of a coordinate axis

How are the graphs made by walking slowly different from the ones made by walking rapidly?

the graphs made by walking faster have steeper slopes than the ones made by walking slowly

walk away from MD

positive slope in a position-vs-time graph means

walk toward MD

Negative slope in a position-vs-time graph means

slow walking

shallow slope in a position graph means

fast walking

steep slope in a position-vs-time graph means

constant velocity (speed and sign (direction))

what type of motion corresponds to a straight line on a position vs. time graph?

increasing or decreasing speed as go

what type of motion corresponds to a curved line on a position vs. time graph?

define velocity

rate of change in position with respect to time

Speed

Units: cm/s, m/s, mi/hr, km/s ...

the magnitude of velocity

what is speed? (in relation with velocity)

Away is above the time axis

How are the velocity-vs-time graphs made by walking away from the MD different from the ones made by walking toward the MD?

Fast is farther away from time axis than slow, which is closer to time axis

How are the velocity-vs-time graphs made by walking slowly different from the ones made by walking rapidly?

moving away

what does it mean in a velocity-vs-time graph: the horizontal line is above the t-axis?

moving toward

what does it mean in a velocity-vs-time graph: the horizontal line is below the t-axis?

moving fast

what does it mean in a velocity-vs-time graph: the horizontal line is far from the t-axis?

moving slow

what does it mean in a velocity-vs-time graph: the horizontal line is close to the t-axis?

how speed and velocity definitions differ?

the speed of an object is how fast the object is moving

motion in the positive direction

For motion along a line, a positive velocity indicates_(2)

motion in the negative direction

For motion along a line, a negative velocity indicates_

absolute value of the velocity

For motion along a line, speed is the _

Question is ambiguous because graph does not show it (no realistic)

What is the velocity of an object in a velocity vs. time graph that shows a vertical line?

-No, because you need time to arrive to next velocity. Thus would be impossible to have a straight line

Is it possible for an object to move in a way that corresponds to an absolutely vertical line on a velocity time graph? Explain

slope

On a X vs. t graph, the velocity is represented by the_

distance (m)

On a y vs x graph, the equation of a straight line is y=mx + b. On a x vs. t graph, what is the name of the variable that corresponds to: y (variable on the vertical axis)

time (s)

On a y vs x graph, the equation of a straight line is y=mx + b. On a x vs. t graph, what is the name of the variable that corresponds to: x (variable on the horizontal axis)

velocity (m/s)

On a y vs x graph, the equation of a straight line is y=mx + b. On a x vs. t graph, what is the name of the variable that corresponds to: m (slope)

initial point from origin (m)

On a y vs x graph, the equation of a straight line is y=mx + b. On a x vs. t graph, what is the name of the variable that corresponds to: b (the vertical intercept)

Distance=velocity X time + initial point from origin

On a X vs. t graph, what is the equation that corresponds to y= mx+b?

steeper slope

What does a position graph looks like for an object that is moving: fast?

shallow slope

What does a position graph looks like for an object that is moving: slow?

line far away from axis

What does a velocity graph looks like for an object that is moving: fast?

line close to axis

What does a velocity graph looks like for an object that is moving: slow?

The velocity changes of signs

How can you tell from a velocity vs. time graph that the moving object has changed direction?

Line is a straight line

How can you tell from a position-time graph that you motion is steady (motion at a constant velocity)?

Line is a horizontal straight line

How can you tell from a velocity vs time graph that your motion is steady?

acceleration

(physics) a rate of change of velocity

Acceleration definition

Acceleration is defined as the rate of change of velocity with respect to time

acceleration formula

acceleration= change in velocity/change in time

displacement

A change in position (delta p).

-If you are speeding up= velocity and acceleration have same signs (+/+ or -/-)

How can you predict the sign of the acceleration of you know the sign of your velocity (your direction of motion) and whether you are speeding up or slowing down? State general rule

Do not move and stay in the same position from MD

What is the general rule of a position vs time graph for: horizontal line?

Move at constant velocity

What is the general rule of a position vs time graph for: straight line?

Move away MD

What is the general rule of a position vs time graph for: Line or curve with positive slope?

Move toward MD

What is the general rule of a position vs time graph for: line or curve with negative slope?

Move constantly fast

What is the general rule of a position vs time graph for: Line or curve with steep slope?

Move constantly slow

What is the general rule of a position vs time graph for: Line or curve with shallow slope?

speeding up

If the sign of the velocity and the acceleration is the same then the object is_______

slowing down

If the sign of the velocity and the acceleration is the opposite then the object is_______

Do not move

What is the general rule of a velocity vs time graph for: horizontal line on t-axis ?

move at same/constant velocity

What is the general rule of a velocity vs time graph for: Horizontal line?

Constant Acceleration

The acceleration of an object is proportional to force (F = ma) - thus, if there is a constant force applied onto an object, the object will accelerate at a constant rate.

Move toward MD (negative direction)

What is the general rule of a velocity vs time graph for: line or curve below the t-axis?

Move away MD (positive direction)

What is the general rule of a velocity vs time graph for: Line or curve above the t-axis?

Move slowly

What is the general rule of a velocity vs time graph for: Line or curve close to t-axis?

move fast

What is the general rule of a velocity vs time graph for: Line or curve far from t-axis ?

slow down

What is the general rule of a velocity vs time graph for: line or curve sloped toward t-axis?

speed up

What is the general rule of a velocity vs time graph for: line or curve sloped away from t-axis?

LACK LAB 7 AND 9

BECAUSE THEY ARE UNDONE FOR THE MOMENT

velocity describes the_

rate at which an object changes position

the ratio of change of velocity

Acceleration is defined as the ratio of_

Acceleration is defined as the_(in a graph)

slope of a velocity vs time graph

m/s^2

An aircraft has a liftoff speed of 33 m/s. What minimum constant acceleration does this require if the aircraft is to be airborne after a take-off run of 240 m? (units)

straight line

An object undergoing constant acceleration has a_velocity graph

-That the velocity is constant (does not change) (ex: remains at 2 m/s)

If a acceleration vs time graph shows a line that remains horizontal over the t-axis, what does this means?

vector

a displacement distinguished by magnitude and direction but not by location.

same

The acceleration vector points in the_direction as the velocity vector for an object that is speeding up and _for an object that is slowing down

is to Change its direction of motion rather than its speed

what is another way to change the acceleration of an object without speeding up and slowing down?

what is the average acceleration formula?

average acceleration= change in velocity/ change in time

the same direction

when an object speeds up, the velocity vector and acceleration vector point in_

instantaneous acceleration (definition and formula)

the average acceleration computer over a very short time interval