The net force acting on the subway car and it's passengers is 3.6 × 10⁴ Newton.
Given the data in the question;
Net force; [tex]F = \ ?[/tex]
From Newton's second law of Motion:
[tex]F = m\ *\ a[/tex]
Where F is the force, m is mass of object and a is the acceleration.
We substitute our given values into the equation
[tex]F = 40000kg\ *\ 0.9m/s^2\\\\F = 36000 kg.m/s^2\\\\F = 3.6*10^4N[/tex]
Therefore, the net force acting on the subway car and it's passengers is 3.6 × 10⁴ Newton.
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