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: fryer (vdf96) Assignment 4.5 graves (6) 1 This printout should have 12 questions. Multiplechoice questions may continue on the next column or page find all choices before answering. 001 10.0 points Assume you are on a planet similar to Earth where the acceleration of gravity is approxi mately 10 m / s 2 . A block of mass 26 kg lies on an inclined plane, as shown. The horizon tal and vertical supports for the plane have lengths of 24 m and 10 m, respectively, and the coefficient of kinetic friction between the plane and the block is 0 . 6. 2 6 k g = . 6 F 24 m 10m The magnitude of the force vector F necessary to pull the block up the plane with constant speed is most nearly 1. bardbl vector F bardbl 244 N correct 2. bardbl vector F bardbl 152 N 3. bardbl vector F bardbl 170 N 4. bardbl vector F bardbl 84 N 5. bardbl vector F bardbl 150 N 6. bardbl vector F bardbl 290 N 7. bardbl vector F bardbl 100 N 8. bardbl vector F bardbl 270 N 9. bardbl vector F bardbl 172 N 10. bardbl vector F bardbl 74 N Explanation: Let : x = 24 m , y = 10 m , m = 26 kg , g 10 m / s 2 , and a = 0 m / s 2 . s x y s = radicalbig x 2 + y 2 = radicalBig (24 m) 2 + (10 m) 2 = 26 m , sin = y s = 10 26 , and cos = x s = 24 26 . Consider the free body diagram for the block N N F mg Perpendicular to the ramp, F net = N F g = 0 N = F g = mg cos . Parallel to the ramp, F net = F g bardbl + F k F = ma = 0 F = F g bardbl + F k = mg sin + k N = mg (sin + k cos ) = (26 kg) (10 m / s 2 ) bracketleftbigg 10 26 + (0 . 6) 24 26 bracketrightbigg = 244 N . 002 10.0 points A block accelerates 3 m / s 2 down a plane in clined at angle 27.0 . fryer (vdf96) Assignment 4.5 graves (6) 2 The acceleration of gravity is 9 . 81 m / s 2 . m k 3 m / s 2 27 Find k between the block and the inclined plane. 1. 0.148 2. 0.510 3. 0.166 correct 4. 1.289 5. 0.853 Explanation: Given : a = 3 m / s 2 , = 27 , and g = 9 . 81 m / s 2 ....
View
Full
Document
This note was uploaded on 12/11/2011 for the course PHYSICS 101 taught by Professor Graves during the Fall '10 term at San Jose City College.
 Fall '10
 Graves
 Physics

Click to edit the document details