Explanation:
Light is not invisible
sound cant travel in a vacuum
Answer:
T= 4.24sec
Explanation:
We are going to use the formula below to calculate.

Where T is period
L is length of rod
g is acceleration due to gravity =
From the problem, the rod is pivoted at 1/4L which means that three quarter of the rod was used for the oscillation. lets call this

= 4.4625m
thus
T= 4.24sec
Atoms are the smallest unit of an element
It is Real,Virtual,The Same Size, Inverted