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The SI units for velocity are ''meters per second (m/s)''.  
The SI units for velocity are ''meters per second (m/s)''.  
===A Computational Model===
Velocity is a quantity that reappears several times when considering the Momentum Principle. The Momentum Principles states that,
<math>{\Delta\boldsymbol{p}}</math> = net force * <math>{\Delta\boldsymbol{t}}</math>
   
   
==Example==
==Example==

Revision as of 17:47, 1 December 2015

Claimed by Stacey Nduati.

Definition
What is velocity?

Velocity is the time rate of change of position of a body in a specified direction. It is a vector quantity that consists of a magnitude and direction. Speed is also the change of position of a body; however, it does not take the object's direction into consideration.

Equation

Average velocity can be calculated using the following equation:

[math]\displaystyle{ \boldsymbol{\bar{v}} = \frac{\Delta\boldsymbol{r}}{\Delta\mathit{t}} }[/math] ,

where [math]\displaystyle{ {\Delta\boldsymbol{r}} }[/math] is the change of position of the object and [math]\displaystyle{ {\Delta\mathit{t}} }[/math] is the change of time.

The SI units for velocity are meters per second (m/s).


A Computational Model

Velocity is a quantity that reappears several times when considering the Momentum Principle. The Momentum Principles states that, [math]\displaystyle{ {\Delta\boldsymbol{p}} }[/math] = net force * [math]\displaystyle{ {\Delta\boldsymbol{t}} }[/math]

Example

Example
3 hour, 230-mile trip

A car takes 3 hours to make a 230-mile trip from Point A to Point B.

Hour 1 Hour 2 Hour 3
Velocity 80 mph north 90 mph north 60 mph north

There are two kinds of velocity in which one must consider: instantaneous velocity and average velocity.

Instantaneous Velocity

Instantaneous velocity is the speed and direction of an object at a particular instant.

Given the example: Each hour has a different instantaneous velocity.

Average Velocity

Average velocity is the net displacement of an object, divided by the total travel time. It is the average of all instantaneous velocities.

Given the example: The average velocity would be (230 miles/3 hours) = 76.67 mph north.

Acceleration

Acceleration is the time rate of change of velocity, with the following equation:

[math]\displaystyle{ \boldsymbol{a} = \frac{\Delta\boldsymbol{v}}{\Delta\mathit{t}} }[/math] ,

where [math]\displaystyle{ {\Delta\boldsymbol{v}} }[/math] is the change of velocity of the object and [math]\displaystyle{ {\Delta\mathit{t}} }[/math] is the change of time.

The SI units for acceleration are meters per second per second (m/s/s). It is also a vector quantity.

Given the example: The acceleration from the 1st hour to the 2nd hour is 10 mph. This indicates a positive acceleration. The acceleration from the 2nd hour to the 3rd hour is -30 mph. This indicates a negative acceleration.

References

1. Chabay, Ruth W., and Bruce A. Sherwood. Matter and Interactions. Hoboken, NJ: Wiley, 2011. Print.

2. "Velocity." Def. 2. Dictionary.com. N.p., n.d. Web. 29 Nov. 2015.

3. Velocity Expression. Digital image. Physics-Formulas. N.p., n.d. Web. 29 Nov. 2015.

4. Animated Car On Road. Digital image. Clip Art Best. N.p., n.d. Web. 29 Nov. 2015.

External links

The Physics Classroom: Speed and Velocity

HyperPhysics: Average Velocity