magnitude of this gravitational force or weight with the symbol W. Because
the body falls with an acceleration g, Eq. 1/1 gives
(1/3)
The weight W will be in newtons (N) when the mass m is in kilograms
(kg) and the acceleration of gravity g is in meters per second squared
(m/s2). In U.S. customary units, the weight W will be in pounds (lb)
when m is in slugs and g is in feet per second squared. The standard values
for g of 9.81 m/s2 and 32.2 ft/sec2 will be sufficiently accurate for our
calculations in statics.
The true weight (gravitational attraction) and the apparent weight
(as measured by a spring scale) are slightly different. The difference,
which is due to the rotation of the earth, is quite small and will be neglected.
This effect will be discussed in Vol. 2 Dynamics.