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A 100 Kg person stands on a bathroom spring scale while riding in an elevator along the Gateway Arch at St. Louis, MO, which we are going to approximate as a triangle. The elevator has (a) upward acceleration at angle α= 30 with value g/4 with the upward vertical during the first half of the journey (b) downward acceleration g/4 again at angle α with downward vertical, what is the weight indicated on the scale in each case?
*Note that the weight will be the same as the normal reaction exerted by the spring scale on the person in the vertical direction.
* Please assume that the spring scale is always level at all points along the ride.
*assume sufficient frictional force avoid horizontal motion of the person inside the elevator.
* Take g=10 m/s2
(i) first solve the problem using Newton’s Laws of motion, in there appropriate form, in the non internal frame of reference of the elevator for both the cases of accelerations.
(ii) Then use D’Alembert’s principle to solve the same problem for both the cases accelerations.
(iii) describe the differences between your thought process while using these two different approaches for solving the same problem and comment on the resulting equations that you obtained.
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