When this near-surface heat is transferred to water, a usable form of geother-energy is created. Geothermal energy is called a renewable energy source because the water is replenished by rainfall, and the heat is continuously produced by the earth. 2.he double-layered core is made up of very hot molten iron surrounding a solid iron center. Estimates of the temperature of the core range from 5,000 to 11,000 degrees Fahrenheit (F). Heat is continuously produced within the earth by the slow decay of radioactive particles that is natural in all rocks.
A galvanometer is a type of sensitive ammeter: an instrument for detecting electric current. It is an analog electromechanical actuator that produces a rotary deflection of some type of pointer in response to electric current through its coil in a magnetic field.
In this demonstration you will use an instrument called a galvanometer. It is an instrument with a bar of iron wrapped with an electrical wire, and a magnet. It detects electrical current. If a wire is connected to this instrument, it can detect if electricity is flowing through the wire. If there is no current through the wire, the needle will move to the left. Similarly, if there is a current flowing through the wire, the needle will move towards the right of the scale. This demonstration should help to give you an idea of the relationship between magnetism and electricity.