A building superintendent twirls a set of keys in a circle at the end of a cord. If the keys have a centripetal acceleration of 115 m/s2 and the cord has a length of 0.36 m, what is the tangential speed of the keys?

To find the tangential speed of the keys, we can use the formula:

\[ a_{\text{centripetal}} = \frac{{v^2}}{{r}} \]

where \( a_{\text{centripetal}} \) is the centripetal acceleration, \( v \) is the tangential speed, and \( r \) is the radius of the circular path.

In this problem, the centripetal acceleration is given as 115 m/s², and the radius of the circular path is given as 0.36 m. We want to find the tangential speed \( v \).

Rearranging the formula, we get:

\[ v = \sqrt{{a_{\text{centripetal}} \cdot r}} \]

Substituting the given values, we have:

\[ v = \sqrt{{115 \, \text{m/s²} \cdot 0.36 \, \text{m}}} \]

\[ v = \sqrt{{41.4 \, \text{m²/s²}}} \]

\[ v = 6.43 \, \text{m/s} \]

So, the tangential speed of the keys is approximately 6.43 m/s.