Answer:
Thermal expansion occurs when an object expands and becomes larger due to a change in that specific object's temperature. Temperature is the average kinetic (basically movement) energy of the molecules in a substance. A higher temperature means that the molecules are moving faster on average.
Well formation of metallic bond depends on free electrons.smaal sized atoms hold their electrons more firmly as compared to large size atoms ,this z due to distance of outer shell electrons by nucleus..in this way no of free electrons affect strength of metallic bond..smaal sized atoms release less free electrons..
When the object slides across the rough surface some of its potential energy will be lost to friction.
<h3>Conservation of mechanical energy</h3>
The law of conservation of mechanical energy states that the total mechanical energy of an isolated system is always constant.
M.A = P.E + K.E
When the object slides across the rough surface, some of the potential energy of the object will be converted into kinetic energy while the remaining potential energy will be converted into thermal energy due to frictional force of the rough surface.
P.E = K.E + thermal energy
Learn more about conservation of energy here: brainly.com/question/166559