The weight is m g, does not change as long as g = 9.81 m/s^2 more or less.
HOWEVER the scale measures the force exerted on the sack of potatoes by the spring in the scale.
When stationary, a = 0, the force on the spring = m g
When accelerating at "a" up we have
Spring force up - m g = m a
so
Spring force = m g + m a
A potato salesman has set up a bootleg potato shop inside an elevator. He sells his potatoes by placing them on a spring scale suspended from the ceiling (like the ones at the grocery store). When the elevator is accelerating upward, is the weight of the potatoes themselves the same, more, or less than they do when the elevator is at rest? How does this compare to the reading on the scale? Think carefully and clearly explain your answer.
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