{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2026-05-26T00:16:20.000Z","description":"Problems submitted by members of the MATLAB Central community.","is_default":true,"created_by":161519,"badge_id":null,"featured":false,"trending":false,"solution_count_in_trending_period":0,"trending_last_calculated":"2026-05-26T00:00:00.000Z","image_id":null,"published":true,"community_created":false,"status_id":2,"is_default_group_for_player":false,"deleted_by":null,"deleted_at":null,"restored_by":null,"restored_at":null,"description_opc":null,"description_html":null,"published_at":null},"problems":[{"id":279,"title":"collision","description":"several cars (n) were involved in this collision, the input matrix (vm) has n rows and two columns, first column for velocity and second column for mass of each car. assume momentum conservation, output final velocity. Example -- vm=[60 2; -30 4], first car velocity (+60) mph, mass 2 tons; second car velocity (-30) mph, mass 4 tons, final velocity is zero.","description_html":"\u003cp\u003eseveral cars (n) were involved in this collision, the input matrix (vm) has n rows and two columns, first column for velocity and second column for mass of each car. assume momentum conservation, output final velocity. Example -- vm=[60 2; -30 4], first car velocity (+60) mph, mass 2 tons; second car velocity (-30) mph, mass 4 tons, final velocity is zero.\u003c/p\u003e","function_template":"function velo = colli(vm)\r\nvelo=0;\r\nend","test_suite":"%%\r\nvm=[60 2; -30 4];\r\nvelo_correct=0;\r\nassert(isequal(colli(vm),velo_correct))\r\n%%\r\nvm=[60 2; -30 4; 100 2];\r\nvelo_correct=25;\r\nassert(isequal(colli(vm),velo_correct))\r\n","published":true,"deleted":false,"likes_count":1,"comments_count":1,"created_by":166,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":147,"test_suite_updated_at":"2012-02-07T13:32:42.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2012-02-07T13:32:42.000Z","updated_at":"2026-04-01T10:54:00.000Z","published_at":"2012-02-07T13:32:42.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eseveral cars (n) were involved in this collision, the input matrix (vm) has n rows and two columns, first column for velocity and second column for mass of each car. assume momentum conservation, output final velocity. Example -- vm=[60 2; -30 4], first car velocity (+60) mph, mass 2 tons; second car velocity (-30) mph, mass 4 tons, final velocity is zero.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"}]}"}],"problem_search":{"problems":[{"id":279,"title":"collision","description":"several cars (n) were involved in this collision, the input matrix (vm) has n rows and two columns, first column for velocity and second column for mass of each car. assume momentum conservation, output final velocity. Example -- vm=[60 2; -30 4], first car velocity (+60) mph, mass 2 tons; second car velocity (-30) mph, mass 4 tons, final velocity is zero.","description_html":"\u003cp\u003eseveral cars (n) were involved in this collision, the input matrix (vm) has n rows and two columns, first column for velocity and second column for mass of each car. assume momentum conservation, output final velocity. Example -- vm=[60 2; -30 4], first car velocity (+60) mph, mass 2 tons; second car velocity (-30) mph, mass 4 tons, final velocity is zero.\u003c/p\u003e","function_template":"function velo = colli(vm)\r\nvelo=0;\r\nend","test_suite":"%%\r\nvm=[60 2; -30 4];\r\nvelo_correct=0;\r\nassert(isequal(colli(vm),velo_correct))\r\n%%\r\nvm=[60 2; -30 4; 100 2];\r\nvelo_correct=25;\r\nassert(isequal(colli(vm),velo_correct))\r\n","published":true,"deleted":false,"likes_count":1,"comments_count":1,"created_by":166,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":147,"test_suite_updated_at":"2012-02-07T13:32:42.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2012-02-07T13:32:42.000Z","updated_at":"2026-04-01T10:54:00.000Z","published_at":"2012-02-07T13:32:42.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eseveral cars (n) were involved in this collision, the input matrix (vm) has n rows and two columns, first column for velocity and second column for mass of each car. assume momentum conservation, output final velocity. Example -- vm=[60 2; -30 4], first car velocity (+60) mph, mass 2 tons; second car velocity (-30) mph, mass 4 tons, final velocity is zero.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"}]}"}],"errors":[],"facets":[[],[{"value":"easy","count":1,"selected":false}]],"term":"tag:\"collision\"","page":1,"per_page":50,"sort":"map(difficulty_value,0,0,999) asc"}}