# Media, Computers & Networks

Description Media, Computers & Networks [BIF_4_MCN] – 2018-19 Tutorial Sheet 2 You are strongly encouraged to record your answers to, and thoughts about, the following and all future exercises in a logbook. Your logbook won’t be assessed, it’s just for your own benefit. You will be allowed to refer to your own “crib sheet” for each of the three multiplechoice tests; you should prepare a single-sided A4 page of notes for each one with text no smaller than the font Arial 10 point (or equivalent). This text is Arial 10 point. If binary numbers are completely new to you, you may find this 10-minute video helpful: https://www.youtube.com/watch?v=vc-9uASeU7I If you are unsure how to convert between decimal, binary and hexadecimal, you may find this 15-minute video helpful: https://www.youtube.com/watch?v=U6d_MsDk2R8 1. a) How many unique bit patterns can be represented using 5 bits? b) How many unique bit patterns can be represented using 9 bits? Number of bits: 1 2 3 4 5 6 7 8 9 10 How many unique bit patterns: 2 4 8 16 — 64 128 256 —- 1024 (or ‘K’) …in other words: 21 22 23 24 25 26 27 28 29 210 2. a) How many unique bit patterns can be represented using 16 bits? LSBU – School of Engineering – BIF_4_MCN – Tutorial 2 2 3. a) Convert the binary number 0111 to decimal. b) Convert the binary number 101110 to decimal. c) Convert the binary number 10010111 to decimal. 4. a) Convert the decimal number 132 to binary. c) Convert the decimal number 199 to binary. d) Convert the decimal number 255 to binary. 5. Convert the hexadecimal number B1C to decimal. Example: What decimal number is represented by 31A16 ? 31A16 = ( 3 × 162 ) + (1 × 161 ) + (10 × 160 ) = (3 × 256) + (1 × 16) + (10 × 1) = 79410 If hexadecimal numbers are completely new to you, you may find this 11-minute Khan Academy video helpful: http://www.youtube.com/watch?v=_97OwCkjh3c 6. Convert the decimal number 164 to hexadecimal. Hint: To convert a decimal number to hexadecimal, first convert it to binary and then write it out in groups of four bits (starting from the least significant bit), and then convert each group to a hex digit. 7. Briefly explain why hexadecimal numbers are often used in preference to binary numbers. 8. In order to print out the number 3.142 on a sheet of paper, which five ASCII codes must be sent to the printer? (You will need to consult a table of ASCII codes to find the binary or hexadecimal equivalent of each character.) 9. Briefly explain why modern IT systems often use Unicode to represent characters rather than ASCII. 10. The novel “Harry Potter and the Deathly Hallows” contains just over 200 thousand words. Estimate whether this amount of ASCII text could be stored on a 650MB CD-ROM. Hint: Estimate the number of letters in an average word; this will allow you to calculate an estimate for the number of characters in the book. [1 character = 8 bits = 1 byte] LSBU – School of Engineering – BIF_4_MCN – Tutorial 2 3 11. A printer has a resolution of 300 dots per inch. How much data needs to be transferred to the printer in order to print a bitmap image measuring 8” x 6” and using 64K colours? (Assume there is no file compression here.) 12. How much memory space would an image consisting of 1024×768 pixels with 24-bit colour require? (Again, assume no file compression.) 13. The 24-bit hexadecimal colour code for crimson is DC143C. How can you tell from this that crimson is a shade of red? 14. What is a vector image? (This is not covered in the lecture notes!)