test","extracted_subject":"PHYSICS","extracted_chapter":"THERMAL PROPERTIES OF MATTER","extracted_topic":"SPECIFIC HEAT CAPACITY","questionPreviewUrl":"https://cdn.pureessence.tech/question-previews/packed_canvases/canvas_355.png?top_left_x=0&top_left_y=0&width=532&height=304&app=solveeit"},"seo_metadata":{"keywords":[]},"doubt_solver_data":{"concept_summary":[]},"embeddings":[],"is_hidden":false,"_id":"66d23c6d70136192204bb081","slug":"a-kettle-with-2-litre-water-at-27sup0supc-is-heate","content":"A kettle with 2 litre water at 27⁰C is heated by operating coil heater of power 1 kW. The heat is lost to the atmosphere at constant rate 160J/sec, when its lid is open. In how much time will water heated to 77⁰C with the lid open ? (specific heat of water = 4.2 kJ/ kg)","options":[{"_id":"68a40b507f15af4716c9a1b4","text":"8 min 20 sec","sequence":0,"isCorrect":true},{"_id":"68a40b507f15af4716c9a1b5","text":"6 min 2 sec","sequence":1,"isCorrect":false},{"_id":"68a40b507f15af4716c9a1b6","text":"14 min","sequence":2,"isCorrect":false},{"_id":"68a40b507f15af4716c9a1b7","text":"7 min","sequence":3,"isCorrect":false}],"correct_answer":"8 min 20 sec","explanation":"P_input = 1 kW = 1000\\(\\frac{J}{\\sec}\\); P_loss = 160 \\(\\frac{J}{\\sec}\\)\n\nP_useful = P_input – P_loss = 840 \\(\\frac{J}{\\sec}\\) **=** \\(\\frac{mS\\Delta T}{t}\\)","question_type":"single_choice","appeared_in":[],"created_at":"2024-08-30T21:41:01.342Z","__v":0,"vector_store_id":"3d159d79-2290-4f8e-8cf9-74e8b66b7504","updated_at":"2024-08-30T21:41:01.342Z","isStarred":false},"params":{"questionSlug":"a-kettle-with-2-litre-water-at-27sup0supc-is-heate"}}]}]]

Question: A kettle with 2 litre water at 27<sup>0</sup>C is heated by operating coil heater of power 1 kW. The...

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