a)

angle with horizontal = 45 degrees
Fy = (100 N)sin 45 = 70.7 N
Fgrav = Weight = 2 Fy = 141 N
m = (Fgrav)/g = 14.1 kg

b)

2. The signs in the two diagrams below hang at equilibrium by means of two cables which are arranged
symmetrically. The mass of the sign and the angle between the cables is indicated. Use trigonometric functions and
force principles to determine the tension in the cables.

a)

angle with horizontal = 30 degrees Fgrav = m*g = 50 N
Fy = Fgrav /2 = 25 N
sin(30) = Fy/Ftens = (25 N)/Ftens
Do some algebra to rearrange the above equation into the form of Ftens = (25 N)/sin(30)
Ftens = 50 N

b)






3. The following diagrams depict a force being applied at an angle in order to accelerate an object across a rough
surface. For each case, determine the values of all missing quantities (Fgrav, Fnorm, Ffrict, Fnet, and acceleration).

a)

b)