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drewdiddy
Oct13-08, 11:59 PM
1. The problem statement, all variables and given/known data

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.


2. Relevant equations

w = mg + ma

3. 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.

alphysicist
Oct14-08, 03:35 AM
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?