Really, that's something that you should decide for yourself. For a start, do you LIKE physics enough, to study a lot of it? You should also check what a physics expert would work in, and whether there are sufficient job opportunities in your country. If you happen to live in the United States (or plan to live there in the future), you can check the information on the OOH (Occupational Outlook Handbook).
There is not "one major branch of physics", there are several.
Yes. Sound is a major concern in physics.
classical physics and (Quantum or modern) Physics
Chemistry, physics, earth science are the major braches of physical science.
Physics is the scientific study of the nature and properties of matter and energy. The major analytical tool for physics is the human brain.
grasslands
newton physics Quantum mechanics
classical physics and (Quantum or modern) Physics
Physics.
physics
The two major divisions in physics are classical and modern physics. The subdivisions on the other hand are mechanics, thermodynamics, acoustics and so many more.
Yes, electricity is a major part of physics from the atom to the cosmos.