A 5 m long bar is pivoted on the right end with a 10 N upward force on the left end. What is the moment of force?

To determine the moment of force acting on the bar, it is essential to understand how torque is calculated. Torque (or moment) is the product of the force applied and the perpendicular distance from the pivot point to the line of action of the force.

In this case, the length of the bar is 5 m, and the force applied is 10 N upward at the left end, which is 5 m away from the pivot point located at the right end. Since the force is acting upwards on the left side while the pivot point is at the right end, the force creates a moment about the pivot.

Calculating the moment:

• The moment is calculated by multiplying the force (10 N) by the distance from the pivot to where the force is applied (5 m).

• Moment = Force × Distance = 10 N × 5 m = 50 Nm.

Considering the direction of the moment, since the force is applied upwards on the left end, it tends to rotate the bar in a counter-clockwise direction about the pivot point at the right end. This defined direction aligns with the conventions used in physics for moment calculations.

Therefore, the correct answer is that the moment of force is 50 Nm counter-clockwise.