Question 8-5.
Torque is the product of force and the lever arm,
A small force can produce a large torque if the lever arm is long. There are many tools in daily life make use of this. Examples are pliers, wrenches, nut crackers etc.
For example:
The torque of force A about axis O is zero even though
the force can be very large. The torque due to force B about
axis O can be large, because it has a long lever arm.
To determine the length of lever arm: Draw a long line along the arrow representing the force vector. This line is called the line of force. The lever arm between the force and a rotating axis is the perpendicular distance between the rotating axis and the line of force:
