Torque is present in everyday happenings, such as operating a doorknob, opening a soda bottle, using a wrench, or pedaling a bicycle. It’s torque that’s getting the job done!
Let’s break it down further. Imagine you’re tightening a bolt, using a wrench. You’ll apply some amount of force to the end of the wrench, which is transferred to the bolt at the other end. This applies torque, or a twisting force, to the bolt.
While horsepower is simply measured in horsepower, torque is typically measured in pounds feet (lb.-ft).
Here’s how that works: If we continue with our wrench example and you imagine you’re using a specific one-foot long wrench to tighten a bolt. Applying one pound of force to the end of that one-foot long wrench exerts one lb.-ft of torque on the bolt. More torque can be applied by adding more weight, or, by using a longer wrench.
The lug nuts that attach the wheels to your car typically need to be tightened to about 100lb.-ft of torque — meaning the operator must apply 100 pounds of force to the end of a foot-long wrench.