In a closed system, the following statements apply:
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Some energy can be changed from one form to another. - This is true, as energy can transform between potential energy, kinetic energy, thermal energy, etc.
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Some energy can be lost to the environment around the system. - This can also be true in practical scenarios where the system is not perfectly closed; however, in a strictly closed system with ideal conditions, this wouldn’t apply.
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The total initial energy will be equal to the total final energy. - This is true in an ideal closed system due to the law of conservation of energy, which states that energy cannot be created or destroyed, only transformed.
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Friction can cause the amount of thermal energy to increase. - This is true, as friction converts kinetic energy into thermal energy, increasing the thermal energy of the system.
The other statements are generally not correct in the context of a closed system:
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Some energy can disappear after it has caused motion. - This does not accurately describe energy behavior in a closed system, as energy is conserved.
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The total initial energy will be greater than the total final energy. - This is not true in a closed system; total energy remains constant.
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Friction can cause energy to be destroyed during the day. - This is incorrect; energy is not destroyed, it is transformed (for example, kinetic energy into thermal energy).
Thus, the selected correct statements are:
- Some energy can be changed from one form to another.
- The total initial energy will be equal to the total final energy.
- Friction can cause the amount of thermal energy to increase.