Question

M Review At the instant A = 50, the boy's center of mass G is momentarily at rest. (Figure 1) Determine his speed when A = 85. The boy has a weight of 75 lb . Neglect his size and the mass of the seat and cords. Express your answer to three significant figures and include the appropriate units. HÅR O a? v= Value Units Figure 1 of 1 > Submit Request Answer 10 ft Part B Determine the tension in each of the two supporting cords of the swing when 0 - 85 Express your answer to three significant figures and include the appropriate units. CHÅR OO? T= Value Units

Answer 1

75 26 32.2 2T = mat E E= ma mat cos O = l=10ft M5 at 75 cos0 32.2 At = 32.2 coso = man mv2 mg sine 2T- > 2T - 75sino 75 v2 32.2\10 dv dt dv dt ds dv -> vdv = ads

> ds = ldo > ds = 10 de 85 32.2 cos0 x 10 do ニ 50° 85 Vdv = 322 coso do 50 85 2.7 sino 322 %3D 50 22 sin 85-sin 50) v- 644(0-996 - 0.766) v?- 148.216 V148.216 Vン Vっ12.174年t/sec. Putting v in er 2T- 75 sin (85') = 75 12.17 32.2 2T= 109 ·21 T = 109.21 54.6 06 16 2.