Can you tell just by looking at something whether it’s hot or cold? Maybe, sometimes, when the thing is steaming hot or freezing cold, but not all the times.

However, you can always tell whether a thing is hot or warm or cool or very cold  by touching it with your hands (or body).
Why is that?
A healthy human body always has temperature of about 98 degrees Fahrenheit(about 36 degress Celsius). Temperature is how hot or cold something is.
Anything that has temperature of more than 98 degrees feels hot.
Anything that has temperature of less than 98 degrees feels cold.

Remember sometimes when you feel sick, your mommy touches your forehead and says you seem hot. When we fall sick, our body temperature becomes higher than 98 degrees. That is why,  if measured, body temperature comes out to be 99 or 100 or 101….