Finding the Force Applied to a Partner Swinging at 4.25 m/s

[jowofoto]

Homework Statement

In the figure the man hanging upside down is holding a partner who weighs 570 N. Assume that the partner moves on a circle that has a radius of 6.50 m. At a swinging speed of 4.25 m/s, what force must the man apply to his partner in the straight-down position?

Homework Equations

Fc=(mv^2)/(t)

The Attempt at a Solution

(570*(4.25)^2) / 6.5

1580 n?

If my logic is wrong, please tell me.

 

[jowofoto]

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