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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

The toRadians and toDegrees functions

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:

Questions & Answers

Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
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
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
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
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Contemporary math applications. OpenStax CNX. Dec 15, 2014 Download for free at http://legacy.cnx.org/content/col11559/1.6
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