This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: reddy (ar38357) Tension and inclined planes clancy (SCI4112) 1 This printout should have 9 questions. Multiplechoice questions may continue on the next column or page find all choices before answering. 001 10.0 points Can an object be in mechanical equilibrium when only a single force acts on it? Explain. 1. None of these 2. No; even one force is too much. There should be no forces acting on an object. 3. No; at least one other force is needed to cancel the action of the first force. correct 4. Yes; a single force is necessary to keep the object in mechanical equilibrium. 5. Yes; the object will act back with an equal and opposite force. Explanation: The sum of the forces acting on an object in equilibrium has to equal zero. Since only a single force acts on the object, it cannot be in equilibrium. 002 (part 1 of 2) 10.0 points The wind exerts a force of 290 N North on a sailboat, while the water exerts a force of 129 N West on the sailboat. What is the magnitude of the net external force on the sailboat? Correct answer: 317 . 397 N. Explanation: Let : F x = F water = 129 N and F y = F wind = 290 N . 290 N 129 N v Scale: 100 m Thus F net = radicalBig F 2 x + F 2 y = radicalBig ( 129 N) 2 + (290 N) 2 = 317 . 397 N . 003 (part 2 of 2) 10.0 points How many degrees west of north is this net external force directed? Correct answer: 23 . 9808 . Explanation: tan = F x F y = tan 1 parenleftbigg F x F y parenrightbigg = tan 1 parenleftbigg 129 N 290 N parenrightbigg = 23 . 9808 , which is 23 . 9808 to the west of north. keywords: reddy (ar38357) Tension and inclined planes clancy (SCI4112) 2 004 10.0 points Two men decide to use their cars to pull a truck stuck in mud. They attach ropes and one pulls with a force of 982 N at an angle of 30 with respect to the direction in which...
View
Full
Document
 Fall '10
 Sontar
 Physics

Click to edit the document details