The food chain may be defined as the sequential tropic levels in which the organism eat other organisms and itself being eaten by other organism. Food chain do not exist in nature.
According to the 10% energy law, the energy is lost from one tropic level to the another tropic level. The 10% energy is available to the next tropic level and the remaining amount of energy is lost as heat. No energy gain occurs as the transfer of energy takes place from the producer to consumer.
Tycho Brache is the person who suggested the sun and moon to orbit the Earth. Danish Nobleman is the person suggested the rest of the planets orbited the sun.
this is because Steel is more difficult to magnetise and demagnetise but an iron core makes a temporary electromagnet because its lose its magnetism when the switch is open and and steel core is used to make a permanent electromagnet
