Here are the essential concepts you must grasp in order to answer the question correctly.
Torque
Torque is a measure of the rotational force applied to an object, calculated as the product of the force and the distance from the pivot point (lever arm). It is expressed in units such as Newton-meters (N·m). In this context, the required torque of 95 m·N indicates the amount of rotational force needed to tighten the bolts.
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Lever Arm
The lever arm is the perpendicular distance from the axis of rotation to the line of action of the force. In this problem, the length of the wrench (28 cm) acts as the lever arm, which amplifies the force applied by the mechanic. A longer lever arm allows for greater torque with less force.
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Force Calculation
To find the force exerted at the end of the wrench, the relationship between torque, force, and lever arm is used: Torque = Force × Lever Arm. Rearranging this formula allows us to calculate the necessary force by dividing the torque by the length of the wrench. This calculation is essential for determining how much force the mechanic needs to apply.
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