Calculate Torque & Forces for Window Washer on Scaffold

[ngay30_07]

A window washer is standing on a scaffold supported by a vertical rope at each end. The scaffold weighs 200 N and is 3.00 m long. What is the tension in each rope when the 700 N worker stands 1.00 m from one end?

My question is that whether there is a normal force exerted on the person by the scaffold? Thanks a lot.

 

[srmeier]

because gravity pulls on the man the scaffold must exert an equal but opposite force up on the man. Otherwise the man would fall to his potential death.

 

[kerimek]

I would like to clarify that there is indeed a normal force exerted on the person by the scaffold. This is due to the fact that the person is standing on the scaffold, which is a solid surface, and therefore, the scaffold exerts a force on the person that is perpendicular to the surface. This normal force is necessary to counteract the gravitational force of the person and scaffold system.

Now, to calculate the torque and forces involved in this scenario, we can use the principles of rotational dynamics. The scaffold, being a 3.00 m long uniform rod, can be considered as a simple lever. The pivot point is at the location where the vertical ropes are attached to the scaffold. The weight of the scaffold (200 N) can be considered as acting at the center of the scaffold, which is 1.50 m from the pivot point.

To calculate the tension in each rope, we can use the equation: Tension = (weight of scaffold + weight of worker) x distance of worker from pivot point / length of scaffold. Plugging in the values, we get: Tension = (200 N + 700 N) x (1.00 m) / (3.00 m) = 300 N.

Therefore, the tension in each rope is 300 N. This means that each rope is pulling with a force of 300 N to support the weight of the scaffold and the worker. Additionally, we can also calculate the torque exerted on the scaffold by the worker using the equation: Torque = Force x distance. In this case, the distance is 1.00 m and the force is 700 N, so the torque exerted by the worker is 700 Nm.

In conclusion, the tension in each rope is 300 N and the torque exerted by the worker on the scaffold is 700 Nm. These calculations are important for understanding the stability and safety of the scaffold system and ensuring that it can support the weight of the worker without tipping over.