Answer
(a) The radial acceleration is $79~m/s^2$
(b) The tension in the cord is $39.5~N$
Work Step by Step
(a) We can find the radial acceleration:
$a_r = \frac{v^2}{r}$
$a_r = \frac{(2.0\pi~m/s)^2}{0.50~m}$
$a_r = 79~m/s^2$
The radial acceleration is $79~m/s^2$
(b) We can find the tension in the cord:
$T = m~a_r$
$T = (0.50~kg)(79~m/s^2)$
$T = 39.5~N$
The tension in the cord is $39.5~N$
