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Screen output

The text shown in Figure 5 should appear in your browser window when you open the html file in your browser.

Figure 5 . Screen output for Listing #3.
Start Script Velocity magnitude = 3.00 miles/hourVelocity angle = 0.00 degrees End Script

Analysis of the code

As before, the script begins by defining the getAngle function, which doesn't require further explanation.

The vectorSum function

As you can see from Listing 3 , this script contains a new function named vectorSum . The purpose of this function is to add two vectors, given the magnitude and angle (in degrees) for each vector asincoming parameters. (The function assumes that both incoming magnitude parameters are expressed in the same units.)

The need to add two vectors occurs so often in physics that I decided to encapsulate the capability into a function that we can copy into future scripts.That will relieve us of the need to rewrite the code each time we need that functionality.

Return an array object

The magnitude and the angle (in degrees) of the resultant vector is returned in a two-element array object, with the magnitude in the element at index 0 and the angle in the element at index 1.I will have a more to say about arrays shortly.

Note that this function calls the getAngle function, which must also be provided in the script.

Subtraction of vectors

The function can also be used to subtract one vector from another. To subtract one vector from another, simply add 180 degrees to the angle for the subtrahend vector before passing the angle to the function.

Adding more than two vectors

Although the function can only be used to add two vectors, it can be called repeatedly to add any number of vectors two at a time.

To use this function to add more than two vectors, add the first two vectors as normal. Then add the vector output from the function to the third vector, etc., until all of the vectors have been included in the sum.

The code in the vectorSum function

Most of the code in the function is the same as code that I have explained in earlier modules. However, there are a couple of lines of code that aredifferent.

The function begins with the following statement:

var vecResult = new Array(2);

The purpose of this statement is to create a two-element array object named vecResult .

What is an array object?

You can think of an array object as a software object containing pigeon holes into which you can store data and from which you can later retrieve that data. This particular arrayobject has two pigeon holes, and they are numbered 0 and 1.

This array object will be used as a container to return the magnitude and angle values for the resultant vector.

Can only return one item

A JavaScript function can only return one item. Up to this point in these modules, that item has consisted of a single numeric value, such as the anglevalue that is returned from the getAngle function.

However, the vectorSum function needs to return two different values. One way to do that is to put those two values in the pigeon holes of an array object andreturn that array object as the one item that can be returned.

Questions & Answers

are nano particles real
Missy Reply
yeah
Joseph
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
Lale Reply
no can't
Lohitha
where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
has a lot of application modern world
Kamaluddeen
yes
narayan
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
Bhagvanji
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
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Source:  OpenStax, Game 2302 - mathematical applications for game development. OpenStax CNX. Jan 09, 2016 Download for free at https://legacy.cnx.org/content/col11450/1.33
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