Why do we warm ourselves by a radiator

We turn on the radiator if we feel cold and warm ourselves in front of it. We become warm because heat travels from the radiator to us, and we absorb its heat energy, causing our own energy content to rise. At root, this explains why we feel more comfortable. 

While this example is elementary in the extreme, its importance lies in the way it illustrates the concept of cause and effect. We would not feel warmer if the radiator 

We are always at the mercy of events as they occur around us. The physical chemist could do nothing if nothing happened chemists look at changes. We say a physical chemist alters variables, such as pressure or temperature. Typically, a chemist causes one variable to change and looks at the resultant response, if any. Even a lack of a response is a form of result, for it shows us what is and what is not a variable. 

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