The specific heat of lead is 140. What does this mean?

This means that in order to heat 1 kg of lead per 1 ° C, 140 J of heat is needed, while the internal energy of lead will increase by 140 J.

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.