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Run the program

I encourage you to use the information provided above to write this program. Experiment with the code, making changes, and observing the results of yourchanges. Make certain that you can explain why your changes behave as they do.

Just for fun, see if you can create a startup screen that displays text similar to the title screen or the credits screen at a movie.

I also encourage you to write the programs described below.

Student programming projects

Copies of these two programs have been posted online for your review (see Resources for the URL) . If you don't find the program using that URL, search the Scratch site for the usernamed dbal.

The program named Logical02

This Scratch program illustrates the use of relational and logical operators to determine if:

  • The value of a variable named LeftOperand is less than or equal to the value of a variable named RightOperand .
  • The value of the variable named LeftOperand is greater than or equal to the value of the variable named RightOperand .

The following four variables are created, displayed on the Stage, and set to zero when the user clicks the green flag:

  1. LeftOperand (a slider variable)
  2. RightOperand (a slider variable)
  3. LessThanOrEqual
  4. GreaterThanOrEqual

A button is also created and displayed on the Stage as shown in Image H .

Image h. program output from the program named logical02.

Missing image.
Image H. Program output from the program named Logical02.

In addition, variables named Equals , GreaterThan , and LessThan are also created but not initialized or displayed. These variables are used by the code to achieve the desired result when the userclicks the button.

The value of each slider variable is set by the user moving the thumb on the slider.

When the user clicks the button, if the left operand is less than or equal to the right operand, the third variable in Image H is set to true. Otherwise, that variable is set to false.

If the left operand is greater than or equal to the right operand, the fourth variable in Image H is set to true. Otherwise it is set to false.

Note, two of the scripts in my version of the program use variables named Equals , GreaterThan , and LessThan whose values are set by the three other scripts. Because I'm unsure as to the orderof execution of the scripts, I inserted a delay of 0.1 second at the beginning of each of those two scripts in an attempt to ensure that the execution of the other threescripts will be completed before an attempt is made to use the values of those variables. This is a crude way to deal with this issue, and is not recommendedfor anything other than demonstration code.

The program named Logical03

This Scratch program is a modification of the program named Logical02. This is a relatively challenging program to write andrequires an understanding of DeMorgan's theorem (see Resources ) .

The behavior of this program is identical to the behavior of the program named Logical02 . However, it is likely that you used the or operator to write that program. This program does not use an or operator.

Instead, this program uses the not operator in conjunction with the and operator along with DeMorgan's theorem to produce behavior that is identical to the program named Logical02 .

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
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.
what is the actual application of fullerenes nowadays?
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.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar 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, Teaching beginners to code. OpenStax CNX. May 27, 2013 Download for free at http://cnx.org/content/col11498/1.20
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