WOLFRAM NOTEBOOK

Moment of a Force about a Point

​
c (cm)
500
tension (N)
50
moment about B = 147.627 Nm
This Demonstration shows how to find the torque, or moment of force, exerted by a rope on a boom
AB
about the point
B
. The torque is a vector quantity, usually written
τ
. You can vary the force and the distance
BC
. When distance is expressed in meters (m) and force in newtons (N), the torque or moment has the dimension newton-meters (Nm).
To find the moment about
B
, multiply the magnitude with the unit vector from
C
to
A
. Next, use the position vector from
B
to the tension
CA
. Finally, the torque about
B
is given by the cross product
τ=rF.

References

[1] F. P. Beer Jr., E. R. Johnston, E. R. Eisenberg, W. E. Clausen, and G. H. Staab, Vector Mechanics for Engineers: Statics and Dynamics, 7th ed., Boston: McGraw Hill, 2003.

Permanent Citation

Wolfram Cloud

You are using a browser not supported by the Wolfram Cloud

Supported browsers include recent versions of Chrome, Edge, Firefox and Safari.


I understand and wish to continue anyway »

You are using a browser not supported by the Wolfram Cloud. Supported browsers include recent versions of Chrome, Edge, Firefox and Safari.