icId":"1b4ec17d-152a-4934-9d9d-e75d6fadc3b9","topicSlug":"friction","cards":[{"id":"025599a2-f6fa-41e1-bc11-1a6b51aa01e3","cardType":"basic","front":"A block moves right across a rough surface. Which way does friction act?","back":"Friction acts to the left.","points":1,"mcqOptions":null},{"id":"e233f7d5-4bc3-4e8c-97d7-2999d6526db2","cardType":"basic","front":"A stationary block would slide down a slope without friction. Which way does friction act?","back":"Friction acts up the slope.","points":1,"mcqOptions":null},{"id":"ed6fd917-1d86-4fca-aeff-f533e211b64a","cardType":"cloze","front":"The friction model is $\\text{[...]}$.","back":"The friction model is $\\boxed{F\\leq \\mu R}$.","points":null,"mcqOptions":null},{"id":"fdc4e8ce-1a17-4321-aeed-177e3d35662d","cardType":"basic","front":"How does static friction respond as an applied force increases below its limiting value?","back":"It adjusts to the value needed for equilibrium.","points":2,"mcqOptions":null},{"id":"deb2bbd1-e030-4172-a7b4-c701ddbb653e","cardType":"cloze","front":"At limiting equilibrium, friction satisfies $\\text{[...]}$.","back":"At limiting equilibrium, friction satisfies $\\boxed{F=\\mu R}$.","points":null,"mcqOptions":null},{"id":"eaf87914-4503-4ebf-8d8b-8280ce062db1","cardType":"basic","front":"Which condition allows you to replace $F\\leq\\mu R$ with $F=\\mu R$ for a stationary body?","back":"The body is on the point of slipping.","points":1,"mcqOptions":null},{"id":"f1f9177c-9fc1-41c3-ac69-39c8a72358b0","cardType":"basic","front":"Why does a rough surface not automatically imply $F=\\mu R$?","back":"Friction may be below its maximum while maintaining equilibrium.","points":2,"mcqOptions":null},{"id":"a5d22c42-ff59-48c1-8033-5bfb25dac522","cardType":"basic","front":"What effect does increasing $\\mu$ have when $R$ is unchanged?","back":"It increases the maximum possible friction.","points":1,"mcqOptions":null},{"id":"d339fccb-740e-4fdd-b717-94501aa9e5d8","cardType":"cloze","front":"The coefficient of friction $\\mu$ is [ ].","back":"The coefficient of friction $\\mu$ is dimensionless.","points":null,"mcqOptions":null},{"id":"3c554590-3f50-4106-baf6-b61ac40209c1","cardType":"basic","front":"When is $R=mg$ valid for a block on a horizontal surface?","back":"When there is vertical equilibrium with no other vertical force components.","points":2,"mcqOptions":null},{"id":"a402e778-5a48-43cb-9c22-695e7478f376","cardType":"cloze","front":"The component of weight down a plane inclined at $\\theta$ is $\\text{[...]}$.","back":"The component of weight down a plane inclined at $\\theta$ is $\\boxed{mg\\sin\\theta}$.","points":null,"mcqOptions":null},{"id":"a38a2977-d70b-4b8e-be90-a3efdfea8901","cardType":"cloze","front":"The component of weight perpendicular into a plane inclined at $\\theta$ is $\\text{[...]}$.","back":"The component of weight perpendicular into a plane inclined at $\\theta$ is $\\boxed{mg\\cos\\theta}$.","points":null,"mcqOptions":null},{"id":"aa739183-6c1d-483d-8876-53b8c6be632d","cardType":"basic","front":"A block is on a slope with no other perpendicular force components. What is $R$?","back":"$R=mg\\cos\\theta$.","points":1,"mcqOptions":null},{"id":"e128d63e-4337-4bef-907b-20f5371cc08f","cardType":"basic","front":"Required friction is less than $\\mu R$. What does this show?","back":"Equilibrium is possible.","points":1,"mcqOptions":null},{"id":"d2aaa553-d84d-428e-93da-a4f496601443","cardType":"basic","front":"Required friction equals $\\mu R$. What state is the body in?","back":"Limiting equilibrium.","points":1,"mcqOptions":null},{"id":"51d88eae-ab0c-4333-91a5-32ed6a0fbcf6","cardType":"basi

3.3.6 Friction (A-level only) Flashcards

3.3.6 Friction (A-level only) Flashcards