Answer: 5.0 meters (choice C)
This length is approximate.
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Step-by-step explanation:
The centripetal acceleration formula we use is
a = (v^2)/r
where v is the linear velocity and r is the radius. The swing moves in a circular path, so the chain acts as the radius. If we can find the radius, then we have found the chain length. The goal is to find r when a = 24 and v = 11
So we have...
a = (v^2)/r
24 = (11^2)/r
24 = 121/r
24r = 121
r = 121/24
r = 5.041667 approximately
r = 5.0 meters when rounding to the nearest tenth
The chain should be approximately 5.0 meters.