Taking summation of moment at a l h d 2 4 ω thus

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Taking summation of moment at A: ( ) L H d 2 4 = ω ⎛ = Thus, Where: T = tension at the support H = tension at the lowest point d = sag ω = weight per unit length L = span or distance between supports 2 Tension at the lowest point : L H 8d ω = 2 2 Tension at the support : L T H 2 ω = + 2 4 3 Approximate lenght of cable : 8d 32d S L L 5L = + d L L/2 L/2 (N/m) ω T T H W L/2 (N/m) ω T L/ 4 L/ 4 W H
Looking for FREE ECE/EE online review? Visit our website @ Contact Us: 0939.926.3210 / 0927.843.8742 GENERAL ENGINEERING AND APPLIED SCIENCES 113 CHAPTER 3 Engineering Mechanics Loading Next Page II. CATENARY (For Symmetrical & Unsymmetrical Supports) Where: T = tension at the support H = tension at the lowest point ω = weight per unit length y = height of the support = c minimum clearance from the ground 1 2 S & S are half lengths of the cable L = span or distance between supports d L x x 2 T 1 T H S S 2 y 1 y c 1 1 1 Tension at the support T : T y = ω 2 2 2 Tension at the support T : T y = ω ( ) 1 2 2 1 1 Tension at the support T : T H S = + ω ( ) ( ) 2 2 2 2 2 Tension at the support T : T H S = + ω 1 1 1 Distance Between supports : S y x cln c + = 2 2 2 Distance Between supports : S y x cln c + = ( ) ( ) ( ) 2 2 2 1 1 Relationship among S,y & c : S y c = ( ) ( ) ( ) 2 2 2 2 2 Relationship among S,y & c : S y c =
Looking for FREE ECE/EE online review? Visit our website @ Contact Us: 0939.926.3210 / 0927.843.8742 114 GENERAL ENGINEERING & APPLIED SCIENCES CHAPTER 3 -MECHANICS GEAS GEAS Loading Next Page FRICTION n FRICTION ON BLOCK F N F tan N = μ φ = μ = o MAXIMUM ANGLE OF INCLINE WITHOUT CAUSING THE BODY TO SLIDE DOWN: 1 tan θ = φ = μ Where, in n & o : F frictional force N normal force P the applied force R total surface reaction coefficient of friction angle of friction angle of the incline = = = = μ = φ = θ = p BELT FRICTION 1 1 2 2 T T e ln T T μφ = = μφ Where: μ = the coefficient of friction φ = angle of contact in radians 1 T = tension in the tight side 2 T = tension in the slack side θ N W φ P f F N = μ N W 1 T 2 T φ
Looking for FREE ECE/EE online review? Visit our website @ Contact Us: 0939.926.3210 / 0927.843.8742 GENERAL ENGINEERING AND APPLIED SCIENCES 115 CHAPTER 3 Engineering Mechanics Loading Next Page o V f V s DYNAMICS I. RECTILINEAR MOTION - (Motion in a Straight Line) Uniform Motion - (constant speed / zero acceleration) s vt = " Where: s = distance v = uniform speed or velocity t = time Uniformly Accelerated Motion - (velocity increases uniformly ) Equations of Motion: 2 o 1 s v t at 2 = ± f o v v at = ± 2 2 f o v v 2as = ± Where: s = distance traveled or displacement o v = original velocity ; ( o v 0, if from rest = ) f v = final velocity ; f (v 0,if to stop) = a = acceleration ( 2 2 m/ s or ft / s ) t = time, (seconds) v v o f v v v = = s o v f v s Use ( ) + if : f o (v v ) > Use ( ) if : f o (v v ) <
Looking for FREE ECE/EE online review? Visit our website @ Contact Us: 0939.926.3210 / 0927.843.8742 116 GENERAL ENGINEERING & APPLIED SCIENCES CHAPTER 3 -MECHANICS GEAS GEAS Loading Next Page II. FREE-FALLING BODY - (Motion Under gravity) Important Equations: 2 o 1 h v t gt 2 = ± f o v v gt = ± 2 2 f o v v 2gh = ± Where: h = height o v = original velocity f v = final velocity g =

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