The special type of periodic motion where the restoring force is proportional to the magnitude of the displacement of the body from the mean position and acts in the direction opposite to the displacement is called simple harmonic motion.
The special type of periodic motion where the restoring force is proportional to the magnitude of the displacement of the body from the mean position and acts in the direction opposite to the displacement is called the simple harmonic motion.
I suspect that I have been following the 2nd format of writing definitions my whole life. However, now I am concerned about its validity. Which one of the two formats is correct? Should there be a "the" at the end (2nd format) or should I not write "the" (1st format)?