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Delta Modern Language Schools
Science department
Grade 6
1st term 2024- 2025

Notes

➢ The measuring unit of heat is called calorie.
➢ If you hit a piece of metal several times by hammer, the piece of metal

becomes warm.
➢ When mixing two substances with different temperatures, so final

temperature at thermal equilibrium equal their average temperature, so the
final temperature of them is between the temperature of the hotter substance
and the temperature of cooler one.
➢ In some cases the final temperature when mixing two substances is less
than their average temperature as there is some thermal energy transfer to
air or the container.
➢ After mixing two substance with different temperatures, the motion of
their molecules changes :
▪ The molecules of the hotter substance become slower after mixing.
▪ The molecules of the cooler substance become faster after mixing.

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