Daily Practice · GCSE Computer Science
August 1990 5-a-day
Every sheet in August 1990
The same date always regenerates the same five questions, so a sheet you print today is the sheet a classmate prints tomorrow.
- 1st August 1990State the difference between lossy and lossless compression.
- 2nd August 1990State the condition that must be met before a binary search can be used on an array.
- 3rd August 1990A logic circuit has inputs C and D. C feeds into a NOT gate; the output of the NOT gate and D feed into an OR gate, giving output Y. Write the Boolean expression for Y and state its value when C = 1 and D = 0.
- 4th August 1990A pseudocode algorithm is: count <- 0, x <- 10, WHILE x > 0, count <- count + 1, x <- x - 3, ENDWHILE, OUTPUT count. Complete a trace table for x and count, laid out as x | count, then state the value output.
- 5th August 1990Which piece of network hardware connects a LAN to another network such as the internet, directing data packets based on IP address?
- 6th August 1990Explain why an interpreter is often preferred while a program is being written.
- 7th August 1990Convert the denary number 45 to hexadecimal.
- 8th August 1990What does the acronym CPU stand for?
- 9th August 1990State what the term malware means.
- 10th August 1990A 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.
- 11th August 1990An uncompressed file is 6000 KB. After lossless compression it is 1500 KB. Calculate the compression ratio in the form n:1 (original size : compressed size).
- 12th August 1990Which of RAM and ROM is volatile, meaning its contents are lost when the power is removed?
- 13th August 1990Which piece of UK legislation controls how organisations must store and use people's personal data?
- 14th August 1990Given x = 5 and y = 8, state whether x < y AND x > 0 evaluates to True or False.
- 15th August 1990State the value returned by LENGTH(word) if word stores the string 'Computer'.
- 16th August 1990Give one reason why RAM on its own is not enough, and a computer also needs secondary storage.
- 17th August 1990State the layer that IP operates in, and describe its job.
- 18th August 1990A password field requires between 6 and 12 characters. State two boundary data values that should be used to test this field.
- 19th August 1990A table called books has fields bookId, title, authorId and copiesAvailable. Write an SQL statement that selects the title of every book with more than 2 copies available.
- 20th August 1990State one function carried out by the operating system of a computer.
- 21st August 1990In computational thinking, what is meant by the term 'decomposition'?
- 22nd August 1990Given A = 1 and B = 1, state the value of A AND B.
- 23rd August 1990State how many different values can be represented using 5 bits, and explain your reasoning.
- 24th August 1990Define a peer-to-peer network.
- 25th August 1990Describe what syntax highlighting is and how it helps a programmer.
- 26th August 1990Convert the denary number 5 to a 4-bit binary number.
- 27th August 1990A CPU has a clock speed of 4.0 GHz. Calculate how many clock cycles it completes in 2 seconds.
- 28th August 1990A simple cipher shifts every letter 2 places forward in the alphabet, wrapping around so Y becomes A and Z becomes B. Encrypt the plaintext CAT using this cipher.
- 29th August 1990Trace this algorithm with data = [4, 9, 2, 9, 7] and state the final output. total = 0; count = 0; for i = 0 to 4: if data[i] > 5 then total = total + data[i] and count = count + 1; next i; print(total, count).
- 30th August 1990A mono sound clip has a sample rate of 4000 Hz and lasts 2 seconds. Calculate the total number of samples taken.
- 31st August 1990State the type of program that is typically stored in ROM.