Daily Practice · GCSE Computer Science
September 2011 - GCSE Computer Science 5-a-day
Every GCSE Computer Science sheet published in September 2011, with answers. Systems, data representation, networks, algorithms and programming.
Every sheet in September 2011
The same date always regenerates the same five questions, so a sheet you print today is the sheet a classmate prints tomorrow.
- 1st September 2011Convert the hexadecimal number 1A to denary.
- 2nd September 2011Convert the denary number 156 to an 8 bit binary number.
- 3rd September 2011Which type of malware can replicate itself and spread across a network without attaching to another program or needing a user to run it?
- 4th September 2011Describe what a nested loop does when it processes a 2D array.
- 5th September 2011An image uses a colour depth of 2 bits per pixel. Calculate the maximum number of different colours it can represent.
- 6th September 2011A CPU's cache has a hit rate of 80%. During a task the CPU makes 4000 requests for data. Calculate the number of cache hits and cache misses.
- 7th September 2011Describe two negative consequences of throwing away old computer hardware instead of recycling it.
- 8th September 2011Write a function called isEven that takes one integer parameter, num, and returns True if num is even and False otherwise.
- 9th September 2011State the pseudocode operator commonly used to join (concatenate) two strings, then show how it joins 'Rev' and 'ision' to produce 'Revision'.
- 10th September 2011A company backs up its files onto magnetic tape cartridges, each with a capacity of 3 TB. The company needs to back up 20 TB of data. Calculate the minimum number of cartridges needed.
- 11th September 2011Give two reasons why network communication is divided into layers.
- 12th September 2011Explain why iterative testing, carried out throughout development, tends to make errors cheaper to fix than relying only on final testing.
- 13th September 2011Define the term 'primary key' as used in a database table.
- 14th September 2011Define the term 'interrupt' as used to describe a signal received by a CPU.
- 15th September 2011An array called items contains [12, 45, 7, 30, 19] at indices 0 to 4. Describe how a linear search would locate the value 30, stating the number of comparisons needed.
- 16th September 2011Evaluate X = NOT A AND B when A = 0 and B = 1.
- 17th September 2011Convert the 8-bit binary number 10110100 directly to hexadecimal by splitting it into nibbles.
- 18th September 2011Give one advantage of a star topology compared with a mesh topology.
- 19th September 2011Explain why an interpreter is often preferred while a program is being written.
- 20th September 2011Add the 8-bit binary numbers 00101101 and 00010011, giving your answer as an 8-bit binary number.
- 21st September 2011State the three stages of the fetch-decode-execute cycle in the order they occur.
- 22nd September 2011State one weakness of a simple shift cipher compared to modern encryption methods used on networks.
- 23rd September 2011A 2D array grid is declared as grid[4][6]. State how many rows and columns it has and how many elements it holds in total.
- 24th September 2011Define the term 'pixel'.
- 25th September 2011Order these from fastest access speed to slowest: RAM, cache, registers, secondary storage.
- 26th September 2011Which piece of UK legislation makes it a criminal offence to gain unauthorised access to a computer system?
- 27th September 2011Evaluate the expression 23 DIV 4.
- 28th September 2011A function is defined as: FUNCTION addTax(price) RETURN price x 1.2 ENDFUNCTION. Another line of code runs: total <- addTax(20) + addTax(30). Trace both function calls and state the final value of total.
- 29th September 2011A 1 TB hard disk drive costs 40 pounds. A 500 GB solid-state drive costs 60 pounds. Calculate the cost per gigabyte of each device, and state which is cheaper per GB. Use 1 TB = 1000 GB.
- 30th September 2011State the layer that IP operates in, and describe its job.