MFGE 201 Engineering Mechanics I Homework IDate of assignment: 08. 10. 2010 Tuesday, till 16:00 pm

Question 1

a) The force acting on the gear tooth is F = 20 N. Resolve this force in two components actingalong the lines aa and bb.

b) The component of force F acting along line aa is required to be 30 N. Determine the magnitudeof F and its component along line bb.

a

ab

b

60 o

80 oF

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Question 2Two forces are applied at the end of a screw eye in order to remove the post. Determine the angle� (0� � � � 90�) and the magnitude of force F so that the resultant force acting on the post isdirected upward and has a magnitude of 750 N.

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Question 3Three forces act on the bracket.

a) Determine the magnitude and direction � of F1 so that the resultant force is directed alongpositive x

0axis and has a magnitude of 1 kN.

b) If F1 = 300 N and � = 20o , determine the magnitude and direction, measured counterclockwisefrom the x

0axis, of the resultant force of the three forces acting on the bracket.

q

30 o

F2=450N

F3=200N45 o

F1

y

x’

x

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Ouestion 4Three forces are applied to the bracket shown below

a) Express each of the three forces acting on the bracket in Cartesian vector form with respect tox� y axes.

b) Determine the magnitude and direction � of F1 so that the resultant force is directed alongpositive x0 axis and has a magnitude of FR = 600 N.

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Question 5Determine the magnitude and coordinate direction angles of the force F acting on the stake.

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Question 6The beam is subjected to the two forces shown. Express each force in Cartesian vector form anddetermine the magnitude and coordinate direction angles of the resultant force.

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Question 7Determine the angle � between the sides of the triangular plate.

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Question 8The force F has a magnitude of 80 N and acts at the midpoint C of the thin rod. Express the forceas a Cartesian vector.

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