Presentation on theme: "Tutorial: Flat & Belt Friction P8.133"— Presentation transcript:
1Tutorial: Flat & Belt Friction P8.133 Engineering 25Tutorial: Flat & Belt Friction P8.133Bruce Mayer, PELicensed Electrical & Mechanical Engineer
2P8-133 → SelfSupporterThe uniform 50-lb plank beam is supported by the rope which is attached to the end of the beam, wraps over the rough peg, and is then connected to the 100-lb block.If the coefficient of static friction between the beam and the block, and between the rope and the peg, µs = 0.4, determine the maximum distance that the block can be placed from A and still remain in equilibrium.Assume the block will not tip.
7MATLAB Results Enter Plank Wt, Wp = 50 Wp = 50 Enter Block Wt, Wb = 100Wb =100Enter Plank Length, WL = 10WL =10Enter CoEff of Static Friction, us = .4us =0.4000the distance d =4.6340
8MATLAB Code % Bruce Mayer, PE % ENGR36 * 25Nov12 % ENGR36_Flat_n_Belt_Friction_Balance_H13e_P8_133_1211.m% The uniform Plank beam of Wt Wp is supported by the rope% which is attached to the end of the beam, wraps over the% rough peg, and is then connected to the Block of Wt Wb% If the coefficient of static friction between the beam &% the block, and between the rope and the peg, µs = 0.2,% determine the maximum distance that the block can be% placed from pt-A and still remain in equilibrium.% * Assume the block will not tip.%% See paper analysis for solution% User to Enter Parametric valuesWp = input('Enter Plank Wt, Wp = ')Wb = input('Enter Block Wt, Wb = ')WL = input('Enter Plank Length, WL = ')L = WL/2; % L is the half-lengthus = input('Enter CoEff of Static Friction, us = ')% calc 90° angle-of-wrap in Radsbeta = pi/2;% use formula to Calc dd = (L/Wb)*(Wp + 2*us*Wb/exp(us*beta));disp(' ')disp('the distance d = ')disp(d)