Step-by-step explanation:
Given that,
Length of the cable is 19.6 m, l = 19.6 m
Let us assume that the angle with vertical rotating pole is 63 degrees.
The total mass of a chair and its occupant is 250 kg.
(a) Let T is the tension in the cable attached to the chair. So,
![T\cos\theta=mg\\\\T=(mg)/(\cos\theta)\\\\T=(250* 9.8)/(\cos(63))\\\\T=5396.58\ N](https://img.qammunity.org/2021/formulas/physics/high-school/mu707pgrtlv1s58lgvvf5vpcw4ts7qey24.png)
(b) The centripetal acceleration acts on it such that,
![(v^2)/(r)=g\tan\theta\\\\v=√(Rg\tan\theta) \\\\v=√(l\sin\theta g\tan\theta)\\\\v=√(19.6* \sin(63)9.8* \tan(63))\\\\v=18.32\ m/s](https://img.qammunity.org/2021/formulas/physics/high-school/op46y786bwavlv4oyoioq10gatf4u4jmq3.png)
Hence, this is the required solution.