A crate with a mass of 175.5 kg is suspended from the end of a uniform boom. The
ID: 2123662 • Letter: A
Question
A crate with a mass of 175.5 kg is suspended from the end of a uniform boom. The upper end of the boom is supported by the tension of 2877 N in a cable attached to the wall. The lower end of the boom pivots at the location marked X on the same wall. Calculate the mass of the boom.
image url: http://s12.postimg.org/sfums167x/image.png
Explanation / Answer
m1 = 175.kg
T = 2877 N
let m2 is the mass and L is the length of boom.
let theta is the angle between T and Horizontal
tan(theta) = 2/11
theta = tan^-1(2/11) = 10.3 degrees
let alfa is the angle between boom and wall
tan(alfa) = 11/6
alfa = tan^-1(11/6) = 61.4 degrres
Net torque acting on the boom is zero.
T*L*sin(alfa+theta) - m2*g*(L/2)*sin(alfa) - m1*g*L*sin(alfa) = 0
T*sin(alfa+theta) - m2*g*sin(alfa)/2 - m1*g*sin(alfa) = 0
2877*sin(71.7) - m2*9.8*sin(61.4) - 175*9.8*sin(61.4) = 0
m2 = (2877*0.949 - 175*9.8*0.88)/(9.8*0.88) = 141.7 kg
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.