How to Calculate the Tension in the Cable
- 1). Multiply the mass of the object attached to the cable by its acceleration. A downward acceleration is negative while an upward acceleration is positive. Call this quantity "x." Assuming a mass of 10 kg and an acceleration of 2 meters per second squared upward, "x" has the value 20 kg times meter per second squared, or 20 newtons. A newton equals one kilogram times one meter per second squared.
- 2). Subtract all the downward forces on the object from the upward forces. Call this quantity "y." Assume you get a result of 10 newtons.
- 3). Subtract "y" from "x" to obtain the tension in the cable in newtons. Completing the exercise you have 20 newtons minus 10 newtons, resulting in a tension of 10 newtons.
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