The earth's magnetic field was flipped by `180^(@)` a million years ago. This flip was relatively rapid and took `10^(5)` years. Then the average change in orientation per year during the flip was closest to,

Options

A. 1 second.
B. 5 seconds.
C. 10 seconds.
D. 30 seconds.

Answer

B

Explanation

1° = 3600 arc sec
average change in orientation per year
`=(180^@)/(10^5)` degree / year
`=(180cc3600)/(10^5)` sec/year
`=1.8xx3.06`
= 6.48 sec/year
Closest option (B)