Weight

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Discussion

An interaction between bodies due to their mass. Weight is the force of gravity acting on an object.

Derive formula from free fall thought experiment.

W = m g

Things that weigh a newton. One newton is about halfway between one-fifth and one-fourth of a pound or the weight of one hundred grams.

metric system	english system
101.972 gf or 0.101972 kgf	0.224809 lb or 3.59694 oz

The "acceleration due to gravity" is also equal to the "gravitational field". Equivalence of inertial and gravitational mass.

Weight is the effect on objects of the acceleration of a reference frame?

mass	weight
Mass vs. Weight
a measure of inertia (resistance to change in motion)	the force of gravity acting on an object due to its mass
invariant (does not change with location)	variable (depends upon location)
scalar (has magnitude only)	vector (directed downward)
kg (SI base unit)	N (SI derived unit)

Can this be made into some kind of problem?
Eight parachutists are to attempt a unique, low-altitude descent in September. They will leap from an altitude of just 75 m -- lower than Big Ben but higher than Nelson's Column …. From exit to full inflation takes around 4 seconds …. That will leave around 30 m of descent with a full canopy in the 75 m drop. The previous lowest jump using military parachutes was from around 130 m, when US troops invaded the Caribbean island of Grenada in 1983.
(Coghlan, Andy. "For the Low Jump." New Scientist. 26 July 1997: 21)
- Answer it.
A problem for Americans only. Verify the often stated rule of thumb that one newton is approximately equal to a quarter pound.
Solution …

Well, here ya go …

F = ma

2.2 lb = (1 kg)(9.8 m/s2)

1 lb = 4.45 N

⅕ < 1 N < ¼ lb

Not quite a quarter pound, but you get the idea.
Write something different.
- Answer it.
Write something completely different.
- Answer it.

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