You can measure stress directly with an instrument the way you measure temperature with a thermometer.

There can be only one normal stress component acting on the surface of an imaginary cut.

If a shear stress component on the left surface of an imaginary cut is upward, then on the right surface it will be downward.

If a normal stress component puts the left surface of an imaginary cut in tension, then the right surface will be in compression.

The correct way of reporting shear stress is = 70 kips.

The correct way of reporting positive axial stress is = +15 MPa.

1 GPa equals 106 Pa.

1 psi is approximately equal to 7 Pa.

A common failure stress value for metals is 10,000 Pa.

Stress on a surface is the same as pressure on a surface as both quantities have the same units.