Question

5. What is common among the following phenomena?

* Blinking of traffic light
* Rotation of blades of fan
* Swinging of pendulum of a clock

a) All are chemical changes
b) All are periodic changes
c) All are undesirable changes
d) All are irreversible changes

Answer 1

All are periodic changes

[And is that a todoroki pfp, I like MHA too

(・∀・) ]