Final answer:
The force applied to a rod to create the greatest torque should be applied at the end furthest from the pivot, maximizing the distance and hence the leverage effect.
Step-by-step explanation:
To result in the greatest amount of applied torque, the force must be exerted as far from the pivot point as possible. In the case of a rod with a pivot at one end, applying the force at the opposite end (5 m away) will produce the maximum torque. Torque (τ) is calculated as τ = rF sin(θ), where ‘r’ is the distance from the pivot point to the point of force application, ‘F’ is the magnitude of the force, and θ is the angle between the force and the lever arm.
When the force is applied perpendicular to the rod, the sine of the angle (θ) is 1, resulting in the formula reducing to τ = rF.
With a 15 N force and a 5 m long rod, the greatest torque is achieved by applying the force at the end of the rod furthest from the pivot.