Big Idea 2

Question 1

What is all digital data represented by at the lowest level?

Answer 1

bits (binary digits)

Question 2

What can bits be grouped to represent?

Answer 2

Abstractions such as numbers, characters, and color.

Question 3

What are number bases such as binary and hexadecimal used to represent?

Answer 3

They are used to represent and investigate digital data.

Question 4

At the lowest levels of abstraction, digital data is represented in binary (base 2), represented using combinations of what to digits?

Answer 4

0 and 1.

Question 5

Why is hexadecimal (base 16) used to represent digital data?

Answer 5

It is used because hexadecimal representation uses fewer digits than binary.

Question 6

Can numbers be converted from any base to another base?

Answer 6

Yes.

Question 7

What representation is used to model the infinite mathematical concept of a number?

Answer 7

A finite one.

Question 8

What limitation in programming languages can result in overflow or other errors?

Answer 8

The fixed number of bits used to represent characters or integers which limits the range of integer values and mathematical operations.

Question 9

What limitation in programming languages can result in round off and other errors?

Answer 9

The fixed number of bits used to represent real numbers (as floating-point numbers) which limits the range of floating-point values and mathematical operations.

Question 10

What might a sequence of bits represent?

Answer 10

Instructions or data (different types of data can be used in different contexts).

Question 11

What does the developing of an abstraction involve?

Answer 11

It involves the removing of details and generalizing functionality.

Question 12

What does an abstraction accomplish?

Answer 12

An abstraction generalizes functionality with input parameters that allow software reuse.

Question 13

What are five ways in which one could express an abstraction?

Answer 13

Constants, expressions statements, procedures, and libraries.

Question 14

What do different programming languages offer?

Answer 14

Different levels of abstraction.

Question 15

What do high-level programming languages typically offer?

Answer 15

They provide more abstractions for the programmer and make it easier for people to read and write a program.

Question 16

What is code in a programming language usually translated into?

Answer 16

Code in another (lower level) language to be executed on a computer.

Question 17

In an abstraction hierarchy, what level of abstractions are placed toward the top and what toward the bottom?

Answer 17

Higher levels of abstractions (more general concepts) are placed toward the top while lower level abstractions (more specific concepts) are placed toward the bottom.

Question 18

What physical layers of computing hardware is used to process binary data?

Answer 18

Gates, chips, and components.

Question 19

What is a logic gate?

Answer 19

A logic gate is a hardware abstraction that is modeled by a Boolean function.

Question 20

What is a chip?

Answer 20

A chip is an abstraction composed of low-level components and circuits that preform a specific function.

Question 21

What are the two ways in which a hardware component’s status can be?

Answer 21

It can be low level like a transistor or high level like a video card.

Question 22

What is hardware made by?

Answer 22

Hardware is built using multiple levels of abstractions such as transistors, logic gates, chips, memory, motherboards, special purpose cards, and storage devices.

Question 23

What are applications and systems made using?

Answer 23

Applications and systems are designed, enveloped, and analyzed using levels of hardware, software, and conceptual abstractions.

Question 24

How can lower-level abstractions make higher-level abstractions?

Answer 24

By combining lower-level abstractions, one can make higher-level abstractions, such as short message services (SMS) or email messages, images, audio files, and videos.

Question 25

What are models and simulations used to represent?

Answer 25

Models and simulations are simplified representations of more complex objects of phenomena.

Question 26

What do models often omit?

Answer 26

Models often omit unnecessary features of the objects or phenomena that are being modeled.

Question 27

What do simulations do? Why are they effective?

Answer 27

Simulations mimic real-world events without the cost or danger of building and testing the phenomena in the real world. Simulations are effective because they can facilitate extensive and rapid testing of models.

Question 28

How do models and simulations assist in the hypothesis making process?

Answer 28

Models and simulations facilitate the formulation and refinement of hypothesis related to the objects of phenomena under consideration.

Question 29

What are the two main results of simulation use?

Answer 29

The results of simulations may generate new knowledge and new hypothesis related to the phenomena being modeled. Simulations also allow hypotheses to be tested without constraints of the real world.

Question 30

What three main things effect the time required for simulations?

Answer 30

Level of detail, quality of the models, and the software and hardware used. (DQS)

Question 31

How can models be changed accurately to reflect the objects or phenomena being modeled?

Answer 31

Through rapid testing.