A bumper jack, used to raise the wheel of an auto-mobile in order to change a tire, is shown in Fig.The mean diameter of the screw is 30 mm, and the pitch ofthe screw is 6 mm. The coefficient of friction between thescrew and the nut is 0.30. Determine the force which mustbe applied to the crank in order toRaise the automobile.200 mm3 kN

Here we have GivenQ=Applied load=3 kNp=pitch of the screw=6 mmμ=Coefficient of friction=0.03R=200…

Answered: A bumper jack, used to raise the wheel…

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.85RP

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A bumper jack, used to raise the wheel of an auto- mobile in order to change a tire, is shown in Fig. The mean diameter of the screw is 30 mm, and the pitch of the screw is 6 mm. The coefficient of friction between the screw and the nut is 0.30. Determine the force which must be applied to the crank in order to Lower the automobile. 200 mm 3 kN
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