5. What is the heat energy generated/emitted by the metal when a 250 kg lump of iron cools from
650° C to 20°C? Specific heat of iron is 449
J/kg
1,459,250,000 J

70,717,500 )
112,250 J
-70,717,500 J

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it

molecules are free to separate from each other and will take on the shape of the container. molecules move completely at random and high speeds. they vibrate in a fixed position and do not move around much. molecules expand to the edge of their container.