Why in solids, sound travels the fastest and heat slowest?
Answer to your question is given below:
Conduction is considered the slowest mode of heat transfer as it moves from particle to particle. Only conduction takes place in solids. Heat Travels slower because each molecule has to keep moving to be hot, so it takes a long time for each molecule to get moving and stay moving and get the next molecule to keep moving with it. Hence, heat travels slowest in solids.