JAMB Physics 2017 Paper

Concept:Moment of a force is the turning effect produced by a force acting at a distance from a pivot.Explanation:Moment of a force is calculated by multiplying the force by the perpendicular distance from the line of action of the force to the pivot.Formula:$$\text{Moment} = \text{Force} \times \text{Perpendicular distance}$$The S.I unit of force is the newton, written as $\mathrm{N}$.The S.I unit of distance is the metre, written as $\mathrm{m}$.Substitute the S.I units into the formula:$$\text{Unit of moment} = \mathrm{N} \times \mathrm{m} = \mathrm{N\,m}$$This unit is called the newton-metre.It is different from the joule because moment is not a form of energy or work.Therefore, the correct S.I unit of moment of a force is newton-metre.Answer:$\mathrm{N\,m}$ (newton-metre), which is Option B.