4-53 The supporting structure of the billboard is attached to the ground by a pin at B, and its rear leg rests on the ground at A. Friction may be neglected. Point G is the center of gravity of the billboard and structure, which together weigh 2800 lb. To prevent tipping over in high winds, a 2370-lb weight is placed on the structure near A, as shown. (a) Compute the magnitudes of the reactions at A and B if the wind load on the billboard is q = 120 lb/ft. (b) Find the smallest wind load q that would cause the structure to tip over.

4-53 The supporting structure of the billboard is attached to the ground by a pin at B, and its rear leg rests on the ground at A. Friction may be neglected. Point G is the center of gravity of the billboard and structure, which together weigh 2800 lb. To prevent tipping over in high winds, a 2370-lb weight is placed on the structure near A, as shown. (a) Compute the magnitudes of the reactions at A and B if the wind load on the billboard is q = 120 lb/ft. (b) Find the smallest wind load q that would cause the structure to tip over.

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 7.72P

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