(4) Determine the forces in members BC and CD of the loaded truss. Ans: BC= 22.4 kN T, CD = 42.4 kN C A 4.5 m B C 16.8 kN 4.5 m 9 kN 2.8 m

A child exerts a force of 27 N on the handle of a small wagon. If the handle of the wagon is directed upwards 20° from the horizontal, find the amount of work done in moving the wagon 20 m horizontally. Round to the nearest N⚫m. The amount of work done is approximately N⚫m.

(4) A vertical 480 N force is applied as shown on the three-bar frame that is supported at pin A and roller B. Determine the magnitudes of the connection forces at pin C and pin E. Ans: C 824 N, E = 561 N 160 mm B 480 N 60 mm D 80 mm E -150 mm- 60 mm 100 mm

4. Determine the resultant of the forces: F, = 440 N [N29°E] and F, = 275 N [S23°E]. Answer:

(5) Determine the force in members AD and BD of the loaded truss. Ans: AD=4170 T, BD = 3590 N C 5m D 6m A 45° B 6m 5m 5000 N

A hiker start from his parked car and walked as follows : 12km due east followed by 8km at 40 north of east , followed by 10km due . Find the components ( along east and north of the net displacement and the magnitude and direction of the displacement

3. A box sitting on a wagon pulled a distance of 27m by a 35N force applied at an angle of 40° to the ground. The box is then lifted a distance of 3.7m and placed on a table by exerting a force of 15N. What is the TOTAL work done?

Calculate the equivalent force-couple system of the shown forces and couples at point B. Calculate the equivalent force-couple system of the shown forces and couples at point A. 4' 2000 lb •A F⚫ B. √25° C. 813 lb.ft 500 lb

(2) For a pair of 20 lb gripping forces, determine the clamping normal force N at each jaw and the pin force at O. Ans: N 80 lb, O= 88.9 lb 16"- 70° 20 lb 20 lb

3. A resistance of 11 Q2 is connected to a battery having an electromotive find: a. current b. battery terminal voltage C. d. force of 6 V and an internal resistance of 1 Q power delivered by electromotive force power delivered to external resistance