1 Fundamentals of algorithms

Question 1

define algorithm

Answer 1

a series of instructions that can perform or execute a specific task

Question 2

define decomposition

Answer 2

a technique where you take a problem and you break it down into smaller parts

Question 3

define abstraction

Answer 3

a technique where you take out unnecessary or extra parts of a problem to make it easier

Question 4

what is the formula for calculating file size?

Answer 4

File size(bytes) = Sample rate * Sample Resolution * time (in seconds) / 8

Question 5

what is the formula for calculating total bytes for a bitmap image?

Answer 5

Total number of bytes for a bitmap image (file size) = colour depth x width x height / 8

Question 6

State 2 effects of increasing the number of pixels the image is made up of

Answer 6

1) You can zoom into the picture more before it becomes pixelated
2) it would increase the file size

Question 7

how are sound waves converted and stored in a computer?

Answer 7

A microphone/sound sensor picks up the sound wave

The wave is converted to an analogue signal

The amplitude/height is measured

These measurements are called samples and take place at regular intervals

These samples are stored as binary values in the computer

Question 8

what will happen if u increase the sample rate?

Answer 8

the file will be truer to its original sound, the file quality will increase.

Question 9

how do you calculate bit rate in sound?

Answer 9

Bit rate = sample rate x bit depth

Question 10

what 3 factors can affect the size of a sound file?

Answer 10

duration, sample rate, and bit depth

Question 11

what is the pseudocode for converting from denary to binary?

Answer 11

Output(“What number do you want to convert?”)
numberD <– USERINPUT
While numberD <> 0 do
Repeat
numberD / 2
Until numberD = 0
Repeat
Remainder <– NumberD MOD 2
Until numberD = 0
End while

Question 12

what is binary shift left basically?

Answer 12

multiplying by powers of two

Question 13

what is binary shift right basically?

Answer 13

dividing by powers of two

Question 14

State the arithmetic effect of applying a left binary shift of 6 followed by a right binary shift of 8 on a binary number

Answer 14

The number would be divided by 2^2

Question 15

State the arithmetic effect of applying a left binary shift of four on a binary number

Answer 15

Multiplying it by 2, 4 times/ Multiply by 2^4