P⃗+T1⃗+T2⃗=0⃗modified cap P with right arrow above plus modified cap T sub 1 with right arrow above plus modified cap T sub 2 with right arrow above equals modified 0 with right arrow above 3. Solving the Puzzle (The Corrected Exercise) Imagine the wires make an angle of 30∘30 raised to the composed with power
Pour illustrer ces théorèmes, prenons un exercice classique que l'on retrouve souvent dans les sujets d'examen. For simplicity, combine weights into one vertical force
Weight of ladder + person: ( W_total = 200 + 600 = 800 , N ), acting downward at center of mass. For simplicity, combine weights into one vertical force at the center of the ladder (since uniform ladder + person at top: center of mass is not at middle, but let's take it at ( \frac23L ) from bottom for person at top. Correction: Person at top = force at top. Better to keep two weights, but for 3-force concurrency, we must find a single resultant weight location. Let's simplify: Person at top → system: ladder + person. CM location: ( x_cm = \fracP\cdot (L/2) \cos\alpha + F\cdot L \cos\alphaP+F ) ( x_cm = \frac200 \times 2.5 \cos60 + 600\times 5 \cos60800 ) ( \cos60 = 0.5 ) → numerator = ( 200\times 1.25 + 600\times 2.5 = 250 + 1500 = 1750 ) ( x_cm = 1750 / 800 = 2.1875 , m ) from bottom along ladder. Total weight = 800 N at that point. Let's simplify: Person at top → system: ladder + person