Question

a body stands on a scale in the elevator if the scale reads 627.2 when the elevator is stationary, what will it read when the elevator is moving upward with an acceleration of 3.0m/s, a constant speed and a deceleration of 2m/s

Answer 1

Putting $m=627.2kg$

scale reading when the elevator is moving upward with an acceleration of $3ms^{-2} = m(a+g)$

$=627.2(3+9.8)=627.2\times 12.8=8028.16N$

At constant speed, $a=0ms^{-2}$

$reading =m(a+g)=627.2(0+9.8) =6146.56N$

At a deceleration of $2ms^{-2},$ $reading=627.2(-2+9.8)=627.2\times 7.8=4892.16N$