The (1) __________ energy is the total (2) __________ and (3) __________ energy of all its particles of the body. The internal energy of a body increases when (4) __________ increases and it changes from (5) __________ to (6) __________ or from liquid to (7) __________. Heat refers to the (8) __________ transferred from one body to another as a result of temperature (9) __________. The process in which heat is transferred is called (10) __________. By doing (11) __________ or (12) __________, internal energy can be (13) __________. The unit of expressing the internal energy of an object is (14) __________. A device that changes thermal energy into mechanical work is referred as (15) __________. When (16) __________ of a heat machine is a lot (17) __________, it becomes contributory to (18) __________, which affects (19) __________ condition and becomes harmful to (20) __________ animals.​