Answer:
a
When the lift is moving upward [tex]F = 1120 \ N[/tex]
b
When the lift is moving downward [tex]F = 820 \ N[/tex]
Explanation:
From the question we are told that
The mass of the man is [tex]m = 100 \ kg[/tex]
The upward acceleration is [tex]a_u = 1.2 \ m/s^ 2[/tex]
The downward acceleration is [tex]a_d = 1.80 \ m/s^2[/tex]
Generally the force which the scale will read when the man is moving downward is according to Newton second law represented as
[tex]F + mg = ma[/tex]
[tex]F = m (g - a_d)[/tex]
Here [tex]g = 10 m/s^2[/tex]
=> [tex]F = 100 (10 - 1.8)[/tex]
=> [tex]F = 820 \ N[/tex]
Generally the force which the scale will read when the man is moving upward is according to Newton second law represented as
[tex]F - mg = ma[/tex]
[tex]F = m (g + a_u)[/tex]
Here [tex]g = 10 m/s^2[/tex]
=> [tex]F = 100 (10 + 1.2)[/tex]
=> [tex]F = 1120 \ N[/tex]
