Why Does the Scale Show 76 kg in the Elevator?

AI Thread Summary
The scale reading of 76 kg in the elevator indicates that the elevator is accelerating upwards, resulting in an apparent increase in weight. To analyze the situation, the force corresponding to the 76 kg can be calculated by multiplying it by the acceleration due to gravity (g). This force represents the net force acting on the person in the elevator. Understanding this relationship helps in correlating the actual mass of 65 kg with the observed weight on the scale. The discussion emphasizes the importance of recognizing how acceleration affects perceived weight in an accelerating frame.
drewdiddy
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Homework Statement



Normal mass is 65kg. I get into an elevator, on a scale in the elevator and it reads 76 kg. Find a along with direction.

Homework Equations



w = mg + ma

The Attempt at a Solution



Obviously the elevator is accelerating upwards due to the apparent increase in mass. However, for the life of me I am having issues setting up this basic problem. I don't need any answers, just a shove in the right direction. How do I correlate the actual mass with the 76 kg? Thank you.
 
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Hi drewdiddy,

What force (acting on you) does the reading of 76kg represent?

In other words, you can find a force from the 76kg reading by multiplying it by g, and that force is acting on you. What force is it?
 

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