OCR GCSE(9-1) Computer Science component 1 SAM



GCSE (9–1) Computer Science J276/02 Computer Systems Sample Question Paper 17th November 2017 AM Time allowed: 1 hour You may not use: ?a calculator* 00 00 0 0 * First name Last name Centre number Candidate number INSTRUCTIONS ?Use black ink.?Complete the boxes above with your name, centre number and candidatenumber.?Answer all the questions.?Write your answer to each question in the space provided.?If additional space is required, use the lined page(s) at the end of thisbooklet. The question number(s) must be clearly shown.?Do not write in the bar RMATION ?The total mark for this paper is 70.?The marks for each question are shown in brackets [ ].?Quality of extended responses will be assessed in this paper in questionsmarked with an *.?This document consists of 12 pages.GCSE (9–1) Computer Science J276/02 Computer Systems Sample Question Paper 17th November 2017 AM Time allowed: 1 hour You may not use: ?a calculator* 00 00 0 0 * First name Last name Centre number Candidate number INSTRUCTIONS ?Use black ink.?Complete the boxes above with your name, centre number and candidatenumber.?Answer all the questions.?Write your answer to each question in the space provided.?If additional space is required, use the lined page(s) at the end of thisbooklet. The question number(s) must be clearly shown.?Do not write in the bar RMATION ?The total mark for this paper is 70.?The marks for each question are shown in brackets [ ].?Quality of extended responses will be assessed in this paper in questionsmarked with an *.?This document consists of 12 pages.ghoward November 2017 J276/02 Turn over […/…/…] DC (…) R10048/191. Frances is writing a program which simulates a dice game played with three ordinary 6-sided dice.(a) When the player rolls the three dice, the player is given points according to the algorithm expressed in the flow diagram below.State the value of the score if the dice rolled are:3 4 5 Score : .........................4 4 4 Score : .........................5 5 6 Score : .........................[3](b) Some rolls of the dice result in a negative score.State a set of three numbers which can be used to test whether the algorithm produces a negative score when it should, and state the expected output for your test data.Set of test data: .........................................................................................................................Expected output: .................................................................................................................. [2]When the dice are rolled, the results are stored in an array called DiceResult.For example, if the first dice shows a 5 then the value of DiceResult(1) becomes 5.(c) Describe what is meant by an array........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ [2](d) State the data type and size of the array DiceResult giving a reason for each.Data type of DiceResult: ...........................................................................................................Reason: .......................................................................................................................................................................................................................................................................................Size of array DiceResult: ..........................................................................................................Reason: .................................................................................................................................................................................................................................................................................. [4]2 A dog that is 5 years old is equivalent to a 42 year old human. Ashok is writing a program which converts the age of a dog to the equivalent age for a human.The program uses the following method:The user inputs age of the dog in years If the age is 2 or less, the human equivalent is 12 times the age If the age is more than 2, the human equivalent is 24 for the first 2 years, plus 6 for every additional year.Write an algorithm to calculate and output the human equivalent of the age of a dog using the method described.............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. [5]3 Charley is writing a program for music students. To make sure that there are no logic errors in the program, Charley uses a test plan.(a) Describe what is meant by a logic error....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... [2](b) The program uses the letters in the following list to represent musical notes.C D E F G A BWhen the user inputs a letter from this list, the program outputs the next three notes in the list.If it gets to the end of the list, it starts again from the beginning, so the next note after B is plete the test plan below by stating, for each input data, the expected outcome and a reason for the test.Input dataExpected outcomeReason for the testCAH[6]4. (a) Describe how a black and white image could be represented as a bitmap in binary. ..................................................................................................................................... ................ ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... ..................................................................................................................................................... ................................................................................................................................................... [3] (b) Give one reason why we use binary to represent data in computers. ...................................................................................................................................................................................................................................................................................................... [1](c) The icon below is represented in a computer's memory as a bitmap image. Four different colours have been used in the icon.How many bits are required to store 1 pixel in this icon image? ........................................................................................................................ [1] (d) Row 1 of the icon is represented in the computer's memory as the bit pattern:What is the bit pattern represented for Row 2 of the icon.[1](e) Calculate the number of bytes required to represent all the pixel data in the icon as a bitmap. Show your working. .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... [2]5. (a)[4](b)(c)[2] 6. Below is an algorithm. Write down all the outputs produced by the algorithm when the value of M input is 3............................................................................................................................................................... .............................................................................................................................................................. ............................................................................................................................................................................................................................................................................................................................ .............................................................................................................................................................. .............................................................................................................................................................. .............................................................................................................................................................. [4]7. (a) Add the following bytes.[2](b) State the problem that will occur if a computer is to store the result as a byte. ................................................................................................................................................... ............................................................................................................................................. [1] (c) The binary number 0110 1110 is stored in a memory location. State the hexadecimal representation of this binary number. ................................................................................................................................................... ............................................................................................................................................. [2] (d) Convert the denary number 55 to an 8 bit binary number ................................................................................................................................................... ............................................................................................................................................. [2] (e) How many bits are there in one byte? ............................................................................................................................................. [1](f) Binary shifting can be used to multiply and divide binary numbers. Complete the following multiplications using the binary shift method to show the result as a binary number.(i) Multiply the following binary number by 4:x 400110101 [2](ii) Divide the following binary number by 8:/ 801010000 [2]8. When recording a sound file on a computer, the sound needs to be sampled.(i) Describe how sampling is used when storing sound....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... [2](ii) Explain the effect of the sampling interval on the size and quality of the sound file recorded............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. [3]9. A taxi uses a computer to communicate with central office and to calculate customers’ fares.(a) The program in the computer uses sequence, selection and iteration.State whether the operations below use sequence, selection or iteration.Performing a series of different set-up operations when the computer is switched on....................................................................................................................................................Beeping repeatedly after a message is sent, until the driver presses a button to show that the message has been read....................................................................................................................................................Deciding whether to use the DayTimeRate or the EveningRate functions to calculate a customer’s fare............................................................................................................................................... [3]10. (a) Explain how ASCII is used to represent text in a computer system.............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. [3] (b) Unicode is also used to represent text in a computer system.Explain the difference between the character sets of Unicode and ASCII........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ [2] ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download