Load, stress, strength, strain and extension

Load is usually expressed as a mass (called weight by normal people) in kg.

To work in scientific units we multiply by the acceleration due to gravity 9.81 meters/sec/sec to get a load in Newtons

If the load on a cable is 500 kg, what is this in Newtons? 4905

If the load on a cable is 580 Newtons, what is this in Kg? 59.1

Your professor weighs about 170 pounds, there are 454 grams in a pound. What does he weigh in kg? 77.2

What would be the load in Newtons if he was dangling from a cable? 757

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Stress = Load/cross sectional area

Load should be in Newtons and area in meters squared so the result is in Pascals.

If the cable had a diameter of 1 centimeter, what is the radius? ½ centimeter.

If it has a diameter of 1 centimeter, what is the cross-sectional area (π r²) ? 0.785 cm²

What is this in square meters? 7.85x10^-5

If the cable has this cross sectional area and your professor dangling from the end, what is the stress? 9.6 MPa

1 MPa = 10⁶ Pascals