The statement that is true concerning an atom would be C. The atomic number of an atom is equal to the number of protons.
Answer:
In a closed system, the total energy is conserved or remains the same as energy transformations take place.
Explanation:
The law of conservation of energy states that energy cannot be created or destroyed but can be transformed from one form to another.
This law of conservation of energy applies only to a closed system. A closed system is a system which does not exchange energy with its surroundings. All forms of energy conversions occurring within a closed system does not result in an increase or decrease of the total energy of the system, rather, energy remains constant. For example, the universe is a closed system in that all forms of energy conversions occurs within it and energy is not exchanged with an external environment. However, the earth is not a closed system as some of the energy it receives from the sun can be radiated out into space. Since it's an open system, its total energy can change.
An example of the use of expansion of materials when they are heated is in
Thermometers. Thermometer is an instrument which is used to measure the
temperature of a place.
It contains mercury which expands as temperature increases. This is used
to accurately determine the temperature of an object.
The disadvantage of expansion of materials when they are heated can be
seen in roads as there is expansion of the surface as a result of heat
exposure leads to roads being rough thereby incurring more costs for
repairs.
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