The tension in the swing's chain at the bottom of the swing is 178.35 N.
The given parameters:
The tension in the swing's chain at the bottom of the swing is calculated as follows;
[tex]T = mg + ma_c\\\\ T= mg + \frac{mv^2}{r} \\\\T = (12 \times 9.8) + (\frac{27 \times 3^2}{4} )\\\\T = 117.6 \ N \ + \ 60.75 \ N\\\\T = 178.35 \ N[/tex]
Thus, the tension in the swing's chain at the bottom of the swing is 178.35 N.
Learn more about tension in vertical circle here: https://brainly.com/question/19904705