To calculate the necessary shaft diameter, we need to determine the maximum torque and maximum bending moment acting on the shaft, and then apply a suitable design theory. Since the figure (Figure Q1)

To calculate the necessary shaft diameter, we need to determine the maximum torque and maximum bending moment acting on the shaft, and then apply a suitable design theory. Since the figure (Figure Q1) showing the exact locations of the pulley C and gear D is not provided, we will make a reasonable assumption for their positions.

Assumption:

• The shaft is simply supported at bearings A and B, which are at the ends of the 1 m length.
• Pulley C is located at $0.3 \text{ m}$ from bearing A.
• Gear D is located at $0.7 \text{ m}$ from bearing A.
• The tangential force from the gear acts horizontally, and the radial force acts vertically.

Given Data:
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