Do the following Binary sums
101+001
111+001
001+100
111+010
011+100
111+111
Category Archives: Homework
Graphic file sizes calculations
We covered this in class last week. Forrester have a good concise article on this subject
Please answer these questions
1. 600 x 300 pixels, 24 bit colour depth
2. 600 x 400, 16 bit colour depth
3. 600 x 600, 24 bit colour depth
4. An image is 6 inches by 8 inches, and has a resolution of 1200 dpi. It has a bit depth of 20.
(a) How many colours can the image store?
(b) What will be the file size of the image?
5. A photograph measures 10 inches by 7 inches, and has a resolution of 400 dpi. The number of colours each pixel can store is 65536.
(a) What is the bit depth of the image?
(b) What will be the file size of the image?
Your “First” Website
Using only notepad and a browser of your choice work through the 7 HTML tasks. Then create a 2 page website with graphics and hyperlinks to show the specifications for the iPad 2. Print out the RAW HTML and make sure you can explain what ALL the tags mean.
Please use the abridged specs.
Homework for 6th March
SQA Past Paper 2007 Section 1
Quick teaser
I lifed this from the 2011 paper it’s question 13
(b) The computer has a maximum addressable memory of 16 Gigabytes. Its address bus width is 32.
(i) Calculate the width of the data bus.
(ii) State why computers do not come with the maximum addressable memory installed.
(iii) State the effect that adding one new line to the address bus would have on the maximum addressable memory.
I thought it was a very good question. I will post the solution to it tomorrow, feel free to comment with your answer but I don’t want you to copy and paste it from the Marking Instructions above.
Homework for w/b 18/12
No homework this week folks make sure your assessment is ready of Tuesday though.
Homework for 14th Dec
- State the purpose of registers in a microprocessor. (1)
- Describe the purpose of two signals found on the control bus. (2)
- An IT manager believes that a Pegasus computer with a 700MHz processor is faster than a Hercules computer with a 650MHz processor. Suggest two reasons why he may be incorrect. (2)
- What is the purpose of a control unit in a CPU? (1)
- If a processor needs an instruction from memory, a read operation is carried out. Describe the steps of the memory read operation with reference to the processor, memory and buses. (4)
- Processor clock speed is one factor which affects system performance. Name one other factor and describe how it affects system performance. (2)
- Calculate the maximum amount of addressable memory that a processor with 24-bit address bus and 16-bit data bus could access. Express your answer in the appropriate units, (3)
Out of 15 – Some of the questions may be difficult but we did touch on them in class and will cover them fully on Wednesday. Blame the wind.
School closure
Well the wind has picked up and we are off school. To prepare for tomorrow’s lesson you can read over the scholar section on computer structure we are working through. Remember, I have a useful report section that allows me to check who has read this and who has not.
You can also head over to revise computing and try their resources.
Finally, there are a few of you still to hand in this weeks programming homework, so you could finish that off.
Plenty to keep you busy and out of the weather, stay safe and I’ll see you tomorrow.
Answers for Homework 7th Dec.
Give two reasons why computers use binary numbers to represent and store data.(2)
- A two state system is easy to represent using electrical signals.
- Fewer rules need to be built into the processor for arithmetic operations.
- It is also easy to represent a two state system on storage devices, eg. CD-ROM
Represent 0111 0100 in decimal.(1)
- 0 + 64 + 32 + 16 + 0 + 4 + 0 + 0= 116
Describe how graphics are stored using a bit-mapped package.(2)
- A bit map is a grid of pixels.
- Each pixel has a binary value representing its colour.
- All pixels in the image are stored even if they have not been assigned a colour.
An image is 4 x 6 inches, has a resolution of 800 dpi and each pixel can display 65,536 different colours. Calculate the storage requirements of this image. Express your answer using suitable units. Show all working. (3)
- (4×800)x(6×800)x16
- =3200x4800x16 = 245760000 bits
- /8 = 30720000 bytes / 1024 =
- 30000 Kb / 1024 = 29.3 Mb
State two advantages of storing the above image as a vector graphic rather than a bit-map.(2)
- The image can be resized without pixelation
- The file size will be much smaller as only a description of how to draw the object is stored, not each pixel.
- Individual objects can be edited without affecting the rest of the image (non-destructive editing)
Represent 13.25 in floating point notation. Express the mantissa in 16-bits and the exponent in 8-bits.(2)
- 1101.01
- Mantissa = 1101 0100 0000 0000
- Exponent = 0000 0100
- 1101 0100 0000 0000 x 2 0000 0100
What is meant by the term lossless compression?(1)
- File size of graphic is reduced without any visible reduction in graphic quality
Explain how the Unicode system overcomes the limitations of ASCII.(1)
- Unicode uses 16-bits compared to ASCII’s 7-bit representation. This allows all the world’s character sets to be represented instead of just 128 characters.
How many different colours could be represented with a bit depth of one byte(1)
- 1 byte = 8 bits
- 28 = 256
- 256 different colours can be represented
Homework for Wed 7th Dec
- Give two reasons why computers use binary numbers to represent and store data.(2)
- Represent 0111 0100 in decimal.(1)
- Describe how graphics are stored using a bit-mapped package.(2)
- An image is 4 x 6 inches, has a resolution of 800 dpi and each pixel can display 65,536 different colours. Calculate the storage requirements of this image. Express your answer using suitable units. Show all working. (3)
- State two advantages of storing the above image as a vector graphic rather than a bit-map.(2)
- Represent 13.25 in floating point notation. Express the mantissa in 16-bits and the exponent in 8-bits.(2)
- What is meant by the term lossless compression?(1)
- Explain how the Unicode system overcomes the limitations of ASCII.(1)
- How many different colours could be represented with a bit depth of one byte(1)
Out of 15.
