omputer-science/aqa/questions","basePath":"/gcse/computer-science/aqa/representing-sound/questions","formulaUrl":null,"initialIndex":38,"initialQuestionWindow":[{"id":"f9915853-a41a-4814-8f86-7dc5eb0ebb30","revisionId":"7f67d958-b79c-48a6-b998-4b98ea6e677b","questionNumber":null,"questionType":"LA","specification":"","difficulty":4,"difficultyBand":"medium","totalMarks":3,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"7b4cc1f8-ca99-4f44-bf3c-a6fee0ee071d","label":null,"content":"An underwater acoustic observatory uses a high-fidelity hydrophone to record marine mammal communication. The system captures mono audio using a sampling rate of $48,000\\text{ Hz}$ and a sample resolution of $24\\text{ bits}$. A continuous recording of a blue whale vocalisation lasts for $250\\text{ seconds}$.\n\nWhat is the minimum file size of this recording in megabytes (MB)?\n\nAssume $1\\text{ kilobyte (kB)} = 1,000\\text{ bytes}$ and $1\\text{ megabyte (MB)} = 1,000,000\\text{ bytes}$.\n\nYou should show your working.","markscheme":"- Shows the correct multiplication of parameters to calculate the total size: $48,000 \\times 24 \\times 250$ (or equivalent incorporating conversion to bytes) M1\n- Converts bits to bytes by dividing by $8$ (or converts $24\\text{ bits}$ to $3\\text{ bytes}$ early in the calculation, e.g., $48,000 \\times 3 \\times 250$) to find $36,000,000\\text{ bytes}$ M1\n- Divides the total bytes by $1,000,000$ to obtain the final answer: $36\\text{ MB}$ A1","marks":3,"order":0,"markingRubric":null,"explanation":null,"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null},{"id":"fab33062-ffe1-4a0b-9161-78da6c4b3373","revisionId":"aeda06ab-c188-494c-8326-a098d93e16ef","questionNumber":null,"questionType":"LA","specification":"An autonomous hydrophone is deployed to capture the low-frequency vocalisation of a blue whale. The device records mono audio at a sampling rate of 6,400 Hz with a sample resolution of 10 bits.","difficulty":4,"difficultyBand":"medium","totalMarks":4,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"6574e285-f848-4fe0-b0be-0296a4d6f204","label":null,"content":"Calculate the minimum file size of a 45-second recording of a whale call. Give your answer in bytes.\n\nYou should show your working.","markscheme":"- Multiplies the sampling rate, sample resolution, and duration: $6,400 \\times 10 \\times 45$ M1\n- Correctly calculates the total file size in bits: $2,880,000$ bits A1\n- Divides the calculated number of bits by 8 to convert to bytes: $\\frac{2,880,000}{8}$ M1\n- States the correct final answer of $360,000$ bytes A1","marks":4,"order":0,"markingRubric":null,"explanation":null,"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null}],"subjectCode":"gcse_computer_science__aqa","summaries":[{"id":"00e5fca2-2c20-4361-ad53-2845355ff80c","difficultyBand":"medium","calculatorUse":null},{"id":"03757f99-c78e-4c15-95d2-7d246d64b845","difficultyBand":"medium","calculatorUse":null},{"id":"091f2dc7-f3d6-4c52-bad1-e6e79af7b5df","difficultyBand":"easy","calculatorUse":null},{"id":"0c929a54-fb8c-41fe-9a48-18276c01c0fa","difficultyBand":"medium","calculatorUse":null},{"id":"0d8663d5-87b2-45bd-92da-293af6b9e0a2","difficultyBand":"easy","calculatorUse":null},{"id":"10a9b4e6-f4c7-4c32-99aa-5c663c2c5057","difficultyBand":"medium","calculatorUse":null},{"id":"14c7131f-247d-468f-8356-fd04452e517e","difficultyBand":"medium","calculatorUse":null},{"id":"31b5f56e-f046-4879-860f-51fdef104a2f","difficultyBand":"easy","calculatorUse":null},{"id":"33727682-159f-40f2-836f-45f8328b26cc","difficultyBand":"easy","calculatorUse":null},{"id":"3c83f6a6-f33f-48f7-9f29-31e779c13544","difficultyBand":"easy","calculatorUse":null},{"id":"3fe979f5-9b5e-4abe-b878-eeef74552366","difficultyBand":"easy","calculatorUse":null},{"id":"5c40e2bf-c4d6-4048-9d1b-b71b147371b2","difficultyBand":"easy","calculatorUse":null},{"id":"614d3734-9beb-4d96-9df7-a3ab6a8379b6","difficultyBand":"medium",

Representing sound

Question 16

Representing sound Questions

Representing sound

Question 16

Representing sound Questions