How to Calculate Net Force on Elevator Moving Downward with Upward Acceleration?

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To calculate the net force on an elevator moving downward with upward acceleration, the equation Fn = ma + mg is used, where Fn is the normal force, m is mass, and g is the acceleration due to gravity. The scenario involves an elevator weighing 600 N, accelerating upward at 2.0 m/s² while moving downward. The calculated normal force is 722.4 N, indicating that the scale reading increases despite the downward motion. This situation can seem contradictory, as the upward acceleration suggests the elevator is slowing down. Clarification is provided that the formula should account for the direction of forces, leading to confusion about whether the weight should increase or decrease.
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Homework Statement


A weighs 600 N on an elevator when it is stationary. Each elevator accelerates according to the specified arrow that is drawn next to it. In all cases where the elevator is moving, it is moving downward.
Find net force, if the elevator is accelerating 2.0 m/s/s upward, even though the elevator is moving downward. Use g = 9.8 m/s/s


Homework Equations


w = mg
F = ma


The Attempt at a Solution


Well this is what i did: F = ma
Fn - mg = ma
Fn = ma + mg
Fn = 61.2(2) + 61.2(9.8)
Fn = 722.4 N
Is that right?
 
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That question seems contradictory. It's accelerating upward, even though it's moving downward? That isn't what Newton's Laws state.
 
well the elevator is moving downward, and if the accleration is upward, doesn't that mean that the elevator is slowing down?
 
My apologies, you're right. I haven't worked dynamics in a while. Regardless, your work looks good.
 
So our scale weight is increasing as we're going down? Shouldnt it be decreasing? Because my teacher said, that the formula should be Fn = ma + -mg
 

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