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How do you find the average speed?
Speed = distance / time
How do you convert MPH to KM
MPH divided by .6214
How do you convert Kilometers to MPH
Kilometers multiplied by .6214
How do you find the meters per second
Multiply the kilometers by 1000 and divide by 3600 since there are 3600 seconds in an hour
What is instantaneous speed?
How fast we are going at a given instant in time
the rate that distance is being covered at a given instant time
Found by using a speedometer
What is the difference between instantaneous speed and average speed?
Average speed is the average speed of the entire trip and instantaneous speed is the speed at one point in the trip
What is average speed?
The average rate at which distance is being covered
How do you find average speed?
dividing the distance traveled by the time required to cover the distance
What is velocity?
The direction and speed
If a car is going 35 MPH around a curve is the velocity constant?
No, since it is changing direction
What are the changed in velocity produced by?
Forces that act upon the car and the most important one is frictional force exerted on the tires by the roads surface
What is a vector?
Velocity is a quantity for both size and direction which are called vectors
Vector quantities include describing motion such a acceleration, velocity, force, and momentum
What is instantaneous velocity
Vector quantity have a size equal to the Instanteous speed at a given instant in time and having a direction corresponding to that of the object’s motion at that instant
What is acceleration
The rate at which velocity changes
What is average acceleration
It is found by dividing the change in velocity by the time it took o complete the change
Acceleration = change in velocity/elapsed time
What is instantaneous acceleration?
The rate at which velocity is changing at a given instant time. It is computed by finding the average acceleration does not change appreciably
How do you find the change in velocity
Subtract the initial velocity from the final velocity. To find the rate of change we need to know the time needed to produce the change.
Can a car be accelerating when its speed is constant
A car is accelerating when it is going at a constant speed around a curve because the velocity is changing and the velocity vector is changing.
What is slope
The slope indicated how rapidly the distance is changing with time at any instant in time
large upward slope means moving forward
What is negative slope
When they car travels backwards the distance from the starting point decreases, the velocity is negative
Downward slope
What is zero slope
Zero velocity, horizontal line
Steep slope
Represents a rapid change in velocity and thus a large acceleration
Can we find the distance traveled from the velocity graph?
For a constant velocity you can get the distance by multiplying the velocity by the time.
D = vt
D - distance
V - velocity
T - time
The distance traveled is equal to the area under the velocity versus time curve.
When the velocity is negative the object is traveling backward and its distance from the starting point its decreasing
What is uniform acceleration?
Unchanging accelerated motion
Occurs when there is a constant force acting on an object
Vo + (a)(t)
Vo - original velocity
A - acceleration
T - time
Average velocity should just be half the final velocity
If the initial velocity is zero the final velocity is acceleration x time multiplying the average velocity yields:
D = ½ at²
Works only if the object starts from rest
D = Vo (t) + ½ (a)(t)²
D - is the distance the object would travel if moved with constant velocity Vo
Note 
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