# 2.7 Game 2302-0370 motion -- uniform and relative velocity  (Page 7/11)

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Store the resulting magnitude in the array object

Once the array object is created, the code in the function shown in Listing 3 is essentially the same as the code used earlier to add two vectors, down to thestatement that begins with:

vecResult[0] = Math.sqrt(Math.pow(vecResultH,2) +...

That statement computes the magnitude of the resultant vector the same way as before, but instead of storing the value of the magnitude in a variable, it isstored in the first pigeon hole of the array object.

The value is directed into the first pigeon hole (technically called element) by the "[0]" that you see following the name of the array object in that statement.

Store the resulting angle in the array object

Immediately thereafter, the statement in Listing 3 that reads

vecResult[1] = getAngle(vecResultH,vecResultV);

computes the angle for the resultant vector and stores it in the second element in the array object (the element identified by the index value 1).

Return the array object for use later

These same index values along with the square brackets "[ ]" will be usedlater to retrieve the magnitude and angle values from the array object.

Finally, the function returns the array object to the calling script by executing the statement that reads

return vecResult;

The main script body

The main script body begins where indicated by the comment in Listing 3 .

The first four statements establish values for the magnitude and direction of the two vectors that represent the train and the man. There is nothing in thosestatements that you haven't seen before.

Note the treatment of the units

However, I encourage you to pay attention to the treatment of units in the comments for the value stored in the variable named vecManMag . The arithmetic in that statement uses two different conversion factors toconvert the value from feet per second to miles per hour.

Once again, working through the units in this fashion can help you to organize your arithmetic correctly.

Call the vectorSum function

The statement that begins

var resultant = vectorSum(vecTrainMag...

calls the new vectorSum function to add the two vectors, passing the magnitude and angle for each vector as parameters.

Store the returned array object in a variable

This statement also declares a new variable named resultant . The array object that is returned from the vectorSum function is stored in this variable.

Once this statement finishes executing, the magnitude and angle of the resultant vector have been computedand saved for later use. (In this script, the only use of those two values is to display them later. However, they will be used in a more significant way inanother exercise later.)

Code to display the results

The call to the vectorSum function is followed by three calls to the document.write method. The first two calls display magnitude and angle values, and the third call simply displays some text to indicate that the script has finishedexecuting.

Displaying the magnitude value

If you examine the statement containing the first call to the document.write method, you will seethat the argument list contains the following expression:

#### Questions & Answers

where we get a research paper on Nano chemistry....?
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
what are the products of Nano chemistry?
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
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
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
ya I also want to know the raman spectra
Bhagvanji
I only see partial conversation and what's the question here!
what about nanotechnology for water purification
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
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?
what is a peer
What is meant by 'nano scale'?
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 ?
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?
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
why we need to study biomolecules, molecular biology in nanotechnology?
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
why?
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
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