The formula for the rotational kinetic energy is

where I is the moment of inertia. This is just mass times the square of the perpendicular distance to the axis of rotation. In other words, the radius of the propeller or this is equivalent to the length of the rod. ω is the angular velocity. We determine I and ω first.

ω = 573 rev/min * (2π rad/rev) * (1 min/60 s) = 60 rad/s
Then,

Option A 3......
... ........
Answer:
1. 18.25 m/s
2. 0 m/s
Explanation:
1.So the centripetal acceleration of the ball at this lowest point must be, taking gravity into account

The speed at this point would then be


2. Similarly, if T = mg, then the centripetal acceleration must be

As the ball has no centripetal acceleration, its speed must also be 0 as well.
Complete Question
The complete question is shown on the first uploaded image
Answer:
the compass direction of the resultant displacement is
south of west
Explanation:
Generally using cosine we can obtain the resultant R as follows

=> 
=> 
We can obtain the direction of the resultant by first using sine rule to obtain angle C as follows

=> ![C= sin ^{-1} [\frac{A * (sin 70)}{R} ]](https://tex.z-dn.net/?f=C%3D%20%20sin%20%5E%7B-1%7D%20%5B%5Cfrac%7BA%20%2A%20%20%28sin%2070%29%7D%7BR%7D%20%5D)
=> ![C = sin ^{-1} [\frac{20 * (sin 70)}{19.48} ]](https://tex.z-dn.net/?f=C%20%3D%20%20sin%20%5E%7B-1%7D%20%5B%5Cfrac%7B20%20%2A%20%20%28sin%2070%29%7D%7B19.48%7D%20%5D)
=> 
Then the direction is obtained as

=> 
=> 
Hence the compass direction of the resultant displacement is
south of west