Answer:
Explanation:
Given
Combined mass of cab and elevator is [tex]M=1510\ kg[/tex]
acceleration of coin with respect to elevator [tex]a_{ce}=-7.4\ m/s^2[/tex]
[tex]a_{ce}[/tex] can be written as
[tex]a_{ce}=a_{cg}-a_{eg}[/tex]
where
[tex]a_{cg}[/tex]=acceleration of coin with respect to ground
[tex]a_{eg}[/tex]=acceleration of elevator with respect to ground
[tex]a_{ce}=a_{cg}-a_{eg}[/tex]
[tex]-7.4=-9.8-a_{eg}[/tex]
[tex]a_{eg}=-9.8+7.4=-2.4\ m/s^2[/tex]
Forces on elevator
[tex]T-Mg=Ma_{eg}[/tex]
[tex]T=M(g+a_{eg})[/tex]
[tex]T=1510\times (9.8-2.4)[/tex]
[tex]T=11,174\ N[/tex]
Here we considered downward direction as negative and upward as positive
