Final answer:
Keep the opening between the blades of a post hole digger in the same direction as the facility running underground. This ensures safety and efficiency.
Step-by-step explanation:
When using post hole diggers, it is important to keep the opening between the blades pointing in the same direction as the facility (or utility) is running. This safety measure helps avoid damaging underground utilities and ensures efficient digging. The post hole digger utilizes simple machines, including levers and wedges, to perform its task. The lever is represented by the handles and the wedge by the blades. To calculate the Ideal Mechanical Advantage (IMA) of the lever, divide the distance from the fulcrum to where the force is applied by the distance from the fulcrum to where the output force is exerted. For the wedge, the IMA would be the length of the wedge divided by its width.