What is a moment and how do I calculate it?

A moment is the turning force that is exerted at right angles (perpendicular) to a pivot.
For example, on a see-saw, the moments would be the forces exerted on each end by the people sat on it. If the see-saw remains still (i.e. at equilibrium), then the sum of the moments is equal to 0.
To calculate a moment, you simply multiply the force in Newtons by the distance in Metres, meaning moments are measured in Newton-metres.
Going back to the example of a see-saw, if you are sat two metres from the pivot and weigh 70kg, then the moment would be:
2 x 70 x g=1372Nm
Here the coefficient for gravity (g) is 9.8 and is used to convert kg into N.
One thing to look out for with moments is when the force is not perpendicular initially, in this case you must make sure to multiply the force by a cos or sin coefficient as well.

JB

Related Maths A Level answers

All answers ▸

Use logarithms to solve the equation 2^(n-3) = 18000, giving your answer correct to 3 significant figures.


Find the stationary points on y = x^3 + 3x^2 + 4 and identify whether these are maximum or minimum points.


The point A lies on the curve y=5(x^2)+9x , The tangent to the curve at A is parralel to the line 2y-x=3. Find an equation to this tangent at A.


(https://qualifications.pearson.com/content/dam/pdf/A-Level/Mathematics/2013/Exam-materials/6666_01_que_20160624.pdf) Question 6.(i)