16.42 seconds will elapse between passing B on the way up and coming back to B on the way down.
<h3>What is the definition of Angular Speed? </h3>
The rate of change of angular displacement is defined as angular speed, and it is stated as follows:
ω = θ t
Where,
θ is the angle of rotation,
t is the time
ω is the angular velocity
Given data;
sin a = 2/5
a=sin(2/5)
a=23°
The linear velocity is the product of the angular velocity and the length.
![\rm v= \omega r \\\\ \omega= 7/5 \\\\ \omega= 1.4 \ rad/sec](https://tex.z-dn.net/?f=%5Crm%20v%3D%20%5Comega%20r%20%5C%5C%5C%5C%20%5Comega%3D%207%2F5%20%5C%5C%5C%5C%20%5Comega%3D%201.4%20%5C%20rad%2Fsec)
The times between the two points are found as;
![\omega = \frac{\triangle \theta }{\triangle t} \\\\ t= \frac{23}{1.4} \\\\ t = 16.42 \ sec](https://tex.z-dn.net/?f=%5Comega%20%3D%20%5Cfrac%7B%5Ctriangle%20%5Ctheta%20%7D%7B%5Ctriangle%20t%7D%20%5C%5C%5C%5C%20t%3D%20%5Cfrac%7B23%7D%7B1.4%7D%20%5C%5C%5C%5C%20t%20%3D%2016.42%20%5C%20sec)
Hence, the time between passing B on the way up and returning to B on the way down will be 16.42 sec.
To learn more about the angular speed refer to the link;
brainly.com/question/9684874
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