For the following two problems: a) Draw a FBD. (be sure to include both forces a
ID: 1653603 • Letter: F
Question
For the following two problems: a) Draw a FBD. (be sure to include both forces and distances) b) Solve for unknown forces c) Draw shear and moment diagrams along the length of the beam, with equations 1) A waiter carrying a to-go bag (1 kg) and balancing a heavy plate (2.1 kg, 22 cm diameter) on his forearm. Ignore the mass of the forearm, wrist, and hand and treat the structure as one single beam. Repeat problem one, including the mass of the forearm, wrist, and hand this time. Assume the forearm, wrist, and hand together are a single simple beam with density 1, 500 kg/m3, radius 0.6 cm.Explanation / Answer
T is the tension on the muscle.
1g = 9.8 N force due the the bag at the end of the fore arm
2.1 g = 20.58 N force due the plate on the fore arm, the force acts at the center of the plate
mass of the fore arm , hand and wrst together = pi*0.0062*0.4*1500 = 0.068 kg
weight of the arm = 0.068*9.8 = 0.67 N
ignore the mass of the arm and take moments of all force about the left end
4*T - 23*20.58 -40*9.8 =0
T = 216.34 N
include the mass of the arm+
4*T - 23*20.58 -40*9.8 -20*0.67=0
T = 219.69 N