Answer: Larmor suggested in 1919 that a self-exciting dynamo could explain the magnetic field of the earth, as well as that of the sun and other stars, but it was Elsasser and Bullard in the 1940s who showed how motion in the liquid core of the earth might produce a self-sustaining magnetic field. By this time seismology and other studies had given a clearer picture of the earth, as having a solid inner core, a liquid outer core, both with a composition more of metal (mainly iron) than rock, and a rocky mantle, all below a thin crust that is all we can directly see. Energy from radioactivity travels outwards as heat, producing thermal convection in the core. It seems that this convection is the cause of the earth's magnetic field, although our knowledge of the core and its dynamics is sketchy. Our knowledge is limited to saying that flow regimes like those that may be occurring in the core can produce self-sustaining dynamos, with characteristics similar to that needed to produce the earth’s magnetic field.
Explanation:
Answer:
C. The sum remains the same.
Explanation:
The sum of the kinetic and potential energy remains the same as the all rolls from point A to E.
We know this based on the law of conservation of energy that is in play within the system.
The law of conservation of energy states that "energy is neither created nor destroyed within a system but transformed from one form to another".
- At the top of the potential energy is maximum
- As the ball rolls down, the potential energy is converted to kinetic energy.
- Potential energy is due to the position of a body
- Kinetic energy is due to the the motion of the body
Because each earthquake can go in different places which the wind moves different and then the earth moves different.
