Answer: 43 degrees
Explanation:
The force of the crutch can be broken into components. The horizontal component of F is the static friction force keeping the crutch from sliding. The vertical component is opposing the weight and is the Normal force. Using the orientation of the angle q, we have the following
fs = Fx = F sin (angle (tita))
N = Fy = F cos (angle(tita))
Maximum angle implies maximum static friction
Therefore,
fsmax = UsN = Us x F cos(angle tita)
Where U = miyu
F sin(angle tita) = Us x Fcos (angle tita)
Sin (angle tita) / cos (angle tita) = Us
Therefore, tan (angle tita) = Us
Angle tita = tan^-1(Us) = tan^-1 (0.931) = 42.95 degrees = 43 degrees
There for Angle tita Max = 43 degrees
The answer should be A weighlifter lifting 100lb. bell bar from his chest to a certain height.
Strength/magnitude would both work
D.) In order to calculate both of them, we must know the "FORCE" on the system.