[填空题]
A ball on the end of a string 1.jhc:5ncjkdf 7 h os/is 5mtib*v7qew6e hqh6 r39+hi:bf7 yat revolved at a uniform rate in a vertical circle of rh veri+6y6:77 bt9 3h5hqtabiemq*wfadius 72.0 cm , as shown in Fig. 5-33. If its speed is 4.00 $\mathrm{~m} / \mathrm{s}$ and its mass is 0.300 kg , calculate the tension in the string when the ball is (a) at the top of its path
(b) at the bottom of its path.
