How Do You Calculate the Force of Tension in a Pendulum Rope?

[enantiomer1]

A bowling ball weighing 71.2 N is attached to the ceiling by a 3.90 m rope. The ball is pulled to one side and released; it then swings back and forth like a pendulum. As the rope swings through its lowest point, the speed of the bowling ball is measured at 4.30 m/s

I've figured out that acceleration = 4.74 m/s²
Now all I need to know is the force of tension in the rope , I've tried F_T= ma
but that isn't working so I'm stuck
anyone know what equation I'm missing?

 

[LowlyPion]

If the question is what is the tension of the rope at the lowest point, then you should be thinking in terms of both mg and mv²/R.

 

[Doc Al]

I've tried F_T= ma
but that isn't working so I'm stuck

That would work if Ft was the only force acting on the ball, but it's not. Set the net force equal to ma.