Take a piece of aluminum wire and quickly bend it several times. Then place your finger on the fold.

Take a piece of aluminum wire and quickly bend it several times. Then place your finger on the fold. Explain how and why the internal energy of the wire has changed.

The metal spoke is hotter because the thermal conductivity of metal is much higher than that of plastic.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.