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mmoadi
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Homework Statement
Person with mass m = 80 kg stands on a scale during a ride in an elevator. How much weight shows on the scale, when the elevator is being moved evenly upwards (downwards) with velocity (speed) v = 1 m/s. How much weight shows on the scale when the elevator starts to move upwards (downwards) or when moving upwards (downwards) starts to stop; if we suppose that at this time the absolute value of acceleration or deceleration is equal to 1 m/s²?
Homework Equations
W= mg
The Attempt at a Solution
Moving with constant velocity of 1 m/s:
Elevator is stopped: a= 0, g= 9.8, W= mg= 80 kg * 9.8 m/s²= 784 N
Elevator is moving up: a= g, W= 2mg= 2 * 80 kg * 9.8 m/s²= 1568 N
Elevator in moving down: a= -g, W= 0
Moving with an acceleration of 1 m/s²:
Elevator is moving up: W= m (g + a)= 864 N
Elevator is moving down: W= m(g - a)= 704 N
Elevator is going down and stopping: W= m(g- (-a))= 864 N
Elevator is going up and stopping: W= m( g+ (-a))= 704 N
Are my conclusions correct?