A young work crew is trying to quickly finish some touch-up painting to complete

Question

A young work crew is trying to quickly finish some touch-up painting to complete a job. Rather than setting up a secure work area, they decide to try a shortcut. Worker A will hold the far end of a 9.96 m work plank which weighs 112 N and is secured with a hinge on the opposite end. Worker B will stand on the plank 4.11 m from worker A. Worker B also brings up his paint can, mc = 3.44 kg, which he places 0.460 m from where he is standing on the plank (between the two workers). Worker A unfortunately needs to supply 483 N of force to hold the end of the plank. How much does worker B weigh? The acceleration due to gravity is g = 9.81 m/s2

Explanation / Answer

the total moments are
sum of M = 0

then

483 X 9.81 - 112 X 9.96 - B X ( 9.96 - 4.11 ) - 3.44 X 9.81 X ( 9.96 - 4.11 + 0.46 ) = 0

4738.23 - 1098.72 - 5.85 B - 33.74 (6.31) = 0

3639.51 - 5.85 B - 212.899 = 0

3426.611 - 5.85 B

3426.611 = 5.85 B

B = 3426.611 / 5.85

B = 585.745 N

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.