e6ea-3fe0-46a7-a9af-38b3d86e9ae6","revisionId":"aca1f6d2-bf2b-4f14-bdb3-0c71d73f7aaf","questionNumber":null,"questionType":"MC","specification":"An autonomous delivery rover on a test track detects an obstacle ahead. The velocity–time graph below shows how its velocity changes from the moment the sensors detect the obstacle at $t = 0\\text{ s}$.\n\n![Velocity-time graph of an autonomous delivery rover](https://assets.mathsgenie.co.uk/aqa-qb/8adecf65-dd4c-48b6-8ddb-a14ff7eb6c93.png)\n\nWhat is the braking distance of the rover?","difficulty":5,"difficultyBand":"medium","totalMarks":1,"sourceTitle":null,"calculatorUse":null,"parts":[],"options":[{"id":"0c631a56-d1c2-44b3-92fd-7274874727d8","content":"$$6.0\\text{ m}$","correct":false,"markscheme":"This is the thinking distance (distance travelled during the reaction time from $t = 0\\text{ s}$ to $t = 0.5\\text{ s}$).","order":0},{"id":"81187742-6f6b-4f07-8ddc-db96cb69e5dd","content":"$$12.0\\text{ m}$","correct":true,"markscheme":"This is the correct braking distance, calculated as the area of the triangle under the deceleration phase from $t = 0.5\\text{ s}$ to $t = 2.5\\text{ s}$.","order":1},{"id":"f1e1de7a-420e-4c2d-b0fd-548accb2ce4e","content":"$$15.0\\text{ m}$","correct":false,"markscheme":"This is the result of incorrectly treating the entire duration from $t = 0\\text{ s}$ to $t = 2.5\\text{ s}$ as a single deceleration triangle.","order":2},{"id":"c5d5d3c0-b929-4db5-bc1d-a7246eb404d8","content":"$$18.0\\text{ m}$","correct":false,"markscheme":"This is the total stopping distance, which is the sum of both the thinking distance and the braking distance.","order":3}],"explanation":null,"firstAttemptFullMarks":null},{"id":"94c54aea-9acf-44b1-a466-842f62fe5ba6","revisionId":"160b9369-5b77-454f-8da1-6d31a33af349","questionNumber":null,"questionType":"LA","specification":"","difficulty":3,"difficultyBand":"medium","totalMarks":6,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"4f8b5a4f-6921-406b-aa06-2346ad5eaada","label":null,"content":"Four cyclists complete different individual journeys, as shown in the table below.\n\n| Cyclist | Distance travelled (km) | Time taken (hours) |\n| :---: | :---: | :---: |\n| **W** | 40 | 2 |\n| **X** | 60 | 3 |\n| **Y** | 60 | 4 |\n| **Z** | 120 | 5 |\n\nUse the information in the table to **describe** and **compare** the motion of the four cyclists.\n\nUse the data to calculate speeds and support your comparisons.","markscheme":"- Uses $\\text{average speed} = \\frac{\\text{distance}}{\\text{time}}$ to calculate at least one speed M1\n- Correctly calculates all four average speeds: $W = 20\\text{ km/h}$, $X = 20\\text{ km/h}$, $Y = 15\\text{ km/h}$, and $Z = 24\\text{ km/h}$ A1\n- States that cyclist Z travelled the furthest ($120\\text{ km}$) and/or cyclist W travelled the shortest distance ($40\\text{ km}$) or took the least time ($2\\text{ hours}$) B1\n- Identifies that cyclists W and X travelled at the same average speed ($20\\text{ km/h}$) B1\n- Identifies that cyclist Z was the fastest ($24\\text{ km/h}$) and/or cyclist Y was the slowest ($15\\text{ km/h}$) B1\n- Compares X and Y: they travelled the same distance ($60\\text{ km}$), but X completed it in a shorter time ($3\\text{ hours}$ vs $4\\text{ hours}$) and therefore had a higher average speed B1","marks":6,"order":0,"markingRubric":null,"explanation":{"methods":[{"id":"calculate_and_compare","label":"Calculate and compare speeds","steps":[{"type":"hyper_latex","block":{"nodes":[{"latex":"\\text{average speed}=\\frac{\\text{distance travelled}}{\\text{time taken}}"},{"latex":"\\text{speed}_W=\\frac{40\\ \\text{km}}{2\\ \\text{h}}=20\\ \\text{km/h}"},{"latex":"\\text{speed}_X=\\frac{60\\ \\text{km}}{3\\ \\text{h}}=20\\ \\text{km/h}"},{"latex":"\\text{speed}_Y=\\frac{60\\ \\text{km}}{4\\ \\text{h}}=15\\ \\text{km/h}"},{"latex":"\\text{speed}_Z=\\frac{120\\ \\text{km}}{5\\ \\text{h}}=24\\ \\text{km/h}"},{"text":"Using this equation to calculate a speed earns M1. All four correct

Motion

Question 34

Motion Questions

Motion

Question 34

Motion Questions