Question

A uniform, 241-N rod that is 2.12 m long carries a 225-N weight at its right end and an unknown weight W toward the left end (see the figure (Figure 1)). When W is placed 54.3 cm from the left end of the rod, the system just balances horizontally when the fulcrum is located 76.2 cm from the right end.

A. Find W.

B. If W is now moved 21.1 cm to the right, how far must the fulcrum be moved to restore balance?
A Review | Constants Part A A uniform, 241-N rod that is 2.12 m long carries a 225-N weight at its right end and an unknown weight W toward the left end (see the figure (Figure 1). When W is placed 54.3 cm from the left end of the rod, the system just balances horizontally when the fulcrum is located 76.2 cm from the right end. Find W. V ALO O ? Figure (< 1 of 1 > W = N Submit Previous Answers Request Answer * Incorrect; Try Again; 5 attempts remaining 225 N Part B

Answer 1

A] Writing torque equation about fulcrum,

225N*0.762 m - W*(2.12m - 0.762m -0.543m) -241N*(2.12/2m -0.762 m) = 0

  225N*0.762 m - W*(2.12m - 0.762m -0.543m) -241*(2.12/2 -0.762) = 0

W =122.25 N

B] Let it be moved x rightward,

  225*(0.762-x) - 122.25*(2.12 -0.762+x -0.543-0.211) -241*(2.12/2 -0.762+x) = 0

x = 0.0438 m  answer