The answer to the question is sound
The back-and-forth movement of electrons is called alternating current. Electrons go back and forth, the direction of their path alternates from one direction to another.
the movement of electrons in one direction is called direct current. The electrons move in a direct, single path without changing directions.
FMRI creates the images or brain maps of brain functioning by setting up and utilizing an advanced MRI scanner in such a way that increased blood flow to the activated areas of the brain shows up on the MRI scan. The MRI scanners do not actually detect blood flow or other metabolic processes.
Answer:
As a result, light travels fastest in empty space, and travels slowest in solids. In glass, for example, light travels about 197,000 km/s.
Explanation: