When a large bone such as the femur is broken, the two pieces are often pulled out of alignment by the complicated combination of tension and compression forces that arise from the muscles and tendons in the leg (see the X­ray image in Figure P3.64A). To realign the bones and allow proper healing, these forces must be compensated for. A method called traction is often employed. If a total tension force of 350 N is applied to the leg to realign the parts of the femur, how much mass m must be attached to the bottom pulley?

To determine the mass m that must be attached to the bottom pulley to apply a tension force of 350 N, we can use the equation:

Tension force (F) = mass (m) x acceleration due to gravity (g)

First, we need to determine the acceleration due to gravity. The standard value for acceleration due to gravity is approximately 9.8 m/s^2.

Using the equation, we rearrange it to solve for mass (m):

m = F / g

Substituting the given values:

m = 350 N / 9.8 m/s^2

m ≈ 35.71 kg

Therefore, approximately 35.71 kg of mass must be attached to the bottom pulley to apply a tension force of 350 N.

To find the mass m that must be attached to the bottom pulley, we need to consider the force of gravity acting on the mass. The force of gravity is equal to the mass times the acceleration due to gravity.

Step 1: Find the weight of the mass
The weight of the mass is equal to the force of gravity acting on it. This can be calculated using the formula:

Weight = mass * acceleration due to gravity

The acceleration due to gravity is approximately 9.8 m/s^2.

Weight = m * 9.8

Step 2: Set up the equation
We are given that the total tension force applied to the leg is 350 N. This tension force is compensated by the weight of the mass. So we can set up the equation:

Tension force = Weight

350 N = m * 9.8

Step 3: Solve for mass
To find the mass m, we can rearrange the equation:

m = Tension force / 9.8

m = 350 N / 9.8

m ≈ 35.71 kg

Therefore, approximately 35.71 kg of mass must be attached to the bottom pulley.

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