Electrons in a hydrogen atom must be in one of the allowed energy levels. If an electron is in the first energy level, it must have exactly -13.6 eV of energy. If it is in the second energy level, it must have -3.4 eV of energy. An electron in a hydrogen atom cannot have -9 eV, -8 eV or any other value in between. Let's say the electron wants to jump from the first energy level, n = 1, to the second energy level n = 2. The second energy level has higher energy than the first, so to move from n = 1 to n = 2, the electron needs to gain energy.
Computed Tomography (CT) Scan of the Head and Face. Guide. A computed tomography (CT) scan uses X-rays to make pictures of the head and face. During the test, you will lie on a table that is attached to the CT scanner, which is a large doughnut-shaped machine.Your head will be positioned inside the scanner. The CT scanner sends X-rays through the head.hy It Is Done. A CT scan of the head is done to: 1  Find the cause of symptoms, such as confusion, paralysis, numbness, vision problems, vertigo, or headaches, that might mean a brain injury, a brain tumor, a ruptured aneurysm, or bleeding inside the head.
A CT scan of the brain may be performed to assess the brain for tumors and other lesions, injuries, intracranial bleeding, structural anomalies such as hydrocephalus, infections, brain function or other conditions, particularly when another type of examination such as X-rays or physical examination are not conclusive. CT scan of the brain may be performed to assess the brain for tumors and other lesions, injuries, intracranial bleeding, structural anomalies such as hydrocephalus, infections, brain function or other conditions, particularly when another type of examination such as X-rays or physical examination are not conclusive.