1. The problem statement, all variables and given/known data A 57.0 kg girl weighs herself by standing on a scale in an elevator. What is the force exerted by the scale when the elevator is descending at a constant speed of 10 m/s? What is the force exerted by the scale if the elevator is accelerating downward with an acceleration of 2.0 m/s2? If the elevator's descending speed is measured at 10 m/s at a given point, but its speed is decreasing by 2.0 m/s2, what is the force exerted by the scale? 2. Relevant equations F=ma, Fs-W=ma 3. The attempt at a solution I got the first part, 9.8(57) = 558.6 N. For the second part I used Fs-W=ma, Fs - 558.6 = (57)2, Fs= 672 N. But that was wrong...? For the 3rd part, I used F=ma, but F= 57 (-2) = -144 N, and that wasn't right either. Help!