- #1
Scirel
- 10
- 0
1.A 110 kg scaffold is 6.8 m long. It is hanging with two wires, one from each end. A 520 kg box sits 2 m from the left end. What is the tension in the left wire?(g = 9.8 m/s2)
For this one I tried using:
6.8 *t=460*9.8*4.8+110*9.8*6.8/2
and solving for t, but I for some reaosn get the wrong answer. What is wrong with my setup?
2.A uniform ladder of mass (m) and length (L) leans against a frictionless wall, see figure. If the coefficient of static friction between the ladder and the ground is 0.48, what is the minimum angle (q) between the ladder and the floor at which the ladder will not slip?
For this one, I tried:
Nf*L/2*sin(90-theta)=Us*Nf*L/2*sin(theta)
and solving for theta, but this seems wrong as well. What is wrong with my setup?
For this one I tried using:
6.8 *t=460*9.8*4.8+110*9.8*6.8/2
and solving for t, but I for some reaosn get the wrong answer. What is wrong with my setup?
2.A uniform ladder of mass (m) and length (L) leans against a frictionless wall, see figure. If the coefficient of static friction between the ladder and the ground is 0.48, what is the minimum angle (q) between the ladder and the floor at which the ladder will not slip?
For this one, I tried:
Nf*L/2*sin(90-theta)=Us*Nf*L/2*sin(theta)
and solving for theta, but this seems wrong as well. What is wrong with my setup?