5.1 Phy1020: brief trigonometry tutorial  (Page 3/20)

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Output for script in Listing 1

When you open the file in your browser, the text shown in Figure 1 should be displayed in the browser window.

Figure 1 . Output for script in Listing 1.
```degrees = 90 : radians = 1.5707963267948965 radians = 1 : degrees = 57.29577951308232radians = 3.141592653589793 : degrees = 180```

Because it will frequently be necessary for us to convert between degrees and radians, I decided to write two functions that we will use to make those conversions. Thatwill eliminate the need for us to stop and think about the conversion (and possibly get it backwards) when writingcode. We will simply call the function that performs the conversion in the required direction.

The toRadians function expects to receive an input parameter describing an angle in degreesand returns the value for that same angle in radians.

The toDegrees function expects to receive an input parameter describing an angle in radiansand returns the value for that same angle in degrees.

Global variables named degrees and radians

The code in Listing 1 begins by declaring global variables named degrees and radians . The variable named degrees is initialized to 90 degrees.

The toRadians function is called to convert that value of degrees to radians. The returned value in radians is stored in the variable named radians .

Display contents of both variables

Then the document.write method is called to display the values contained in both variables, producing the first line of output text shown in Figure 1 .

Modify variable contents, convert, and display again

Following that, a value of 1 is assigned to the variable named radians . The toDegrees function is called to convert that value to degrees, and the result is stored in the variable named degrees .

Once again, the document.write method is called to display the current contents of both variables, producing the second line of output textshown in Figure 1 .

One more time

Finally, the mathematical constant, PI, is stored in the variable named radians . Then that value is converted to degrees and stored in thevariable named degrees . The current values in both variables are displayed, producing the last line of output text shown in Figure1.

And the results were...

As you can see from Figure 1 ,

• Ninety degrees is equal to 1.57 radians
• One radian is equal to 57.296 degrees
• 3.14 (PI) radians is equal to 180 degrees

A template

You might want to save your html file as a template for use with future exercises that require conversions between radians and degrees. This will beparticularly useful when we write scripts that use JavaScript's built-in trigonometric methods. Those methods deal with angles almost exclusively inradians while we tend to think of angles in degrees. We will use these two functions to perform conversions between degrees and radians whenrequired.

Sine, cosine, and tangent

An exercise involving a right triangle

For the next exercise, I would like for you to create a right triangle on your graph board by placing pushpins at the following coordinates:

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
anyone know any internet site where one can find nanotechnology papers?
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
what does nano mean?
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
it is a goid question and i want to know the answer as well
Maciej
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
for screen printed electrodes ?
SUYASH
What is lattice structure?
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
how did you get the value of 2000N.What calculations are needed to arrive at it
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