Total Utility in Economics

          In economics, Total utility refers to the amount of satisfaction obtained from our entire consumption of a product. By contrast, marginal utility refers to the amount of satisfaction you get from consuming the last unit of a product. Economists sometimes speak of a law of diminishing marginal utility, meaning that the first unit of consumption of a good or service yields more utility than the second and subsequent units, with a continuing reduction for greater amounts. The relationship between total and marginal utility is:

Marginal utility = change in total utility / change in quantity

This formal not only can explain why we want to surf the net but also why we stop surfing the net.

         I always surf the net when I am sick of studying. Surfing the net and watch some TV shows or read a novel can help me relax myself and enjoy the show or novel. Internet is a really convenient tool for me to use and enjoy. But the more time I spend online, the less satisfaction I have, because my eyes feel tired and also I lose my interest in TV shows and novels. I always enjoy surfing the net at the first a few hours, but my enjoyment decline when I surf the net the longer.

           The total and marginal utility can change as I spend more time surfing the Net. Although total utility usually increases as I spend more time surfing the net, but marginal utility tends to decline as I spend more time on line.  If marginal utility would become negative, the total utility will decline. The law of diminishing marginal utility states that each successive unit of a good consumed yields less additional utility. I think the situation explain the law of diminishing marginal utility very well, the more time I spend on line, the less satisfaction I obtain.

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