To test the effects of high acceleration on the human body, the National Aeronautics and Space Administration (NASA) constructed a large centrifuge at the Manned Spacecraft Center in Houston. Astronauts are placed in a capsule that moves in a circular path with a radius of $15 \mathrm{~m}$. If the astronauts in this centrifuge experience a centripetal acceleration $9.0$ times that due to gravity, what is the linear speed of the capsule?