State the relationship between joules and calories

How to convert joules to calories (cal)

state the relationship between joules and calories

One joule is the amount of work or energy produced when a force of 1 newton acts through a distance of 1 meter. One calorie is the amount of. The most common units of heat are BTU - British Thermal Unit, Calorie and Joule. units for heat are. BTU (Btu) - British Thermal Unit - also known as a "heat unit" in United States; Calorie; Joule Converting between heat and energy units. State the relationship between joules and calories The KGB Agent answer: A calorie equals approximately joules. To convert calories to.

Old terminology tends to linger, particularly when one of the countries that stuck with the older measures is the United States of America.

state the relationship between joules and calories

That said, if you are interested in tracking the energy levels in your food, it might be worth switching your thinking over to kilojoules for the same reason it's easier to think in kilometres when travel long-distances in Australia - all the official signs and food packaging use those measurements, and you don't have to rely on someone translating them for you. Regardless of the term you use, here's what really matters Whether you use calories or kilojoules, what really matters is how they're related to achieving and maintaining a healthy weight.

You naturally take in energy from the food that you eat. You naturally burn off energy through the process of living your life, with everything from sleeping to lifting weights taking something from your energy reserves. Your exact daily energy requirements will vary based on your age, height, gender, and general level of physically activity, but weight gain tends to happen when you consume more energy than you expend.

state the relationship between joules and calories

If you're curious about what your daily energy requirements are, you can use this calculator to find out. Learning your energy requirements is your first step, but your second is learning to recognise that not all kilojoules are created equal. A single chocolate bar can contain as many kilojoules as a serve of healthy mixed-veggie mashbut the latter will see you consuming approximately grams of nutrient-rich vegetables that will help leave you feeling full, compared to just 40 grams of sugar-rich chocolate.

The transfer of energy due to temperature differences is called heat. For example, if you hold an ice cube in your hand, the ice cube slowly melts as energy in the form of heat is transferred from your hand to the ice. As your hand loses energy, it starts to feel cold. Because of their interrelationships, energy, work, and heat have the same units. The SI unit of energy, work, and heat is the joule J. A joule is a tiny amount of energy.

Many processes occur with energy changes in thousands of joules, so the kilojoule kJ is also common.

Another unit of energy, used widely in the health professions and everyday life, is the calorie cal.

State the relationship between joules and calories? | Yahoo Answers

Although the joule is the proper SI unit for energy, we will use the calorie or the kilocalorie or Calorie in this chapter because they are widely used by health professionals. Neither the g-calorie nor the kcal is an SI unit. However, unlike other scientists, nutritionists are involved in public education concerning energy balance, and the U. Indeed, the Calorie on U. At present, it is not helpful to ask lay people to set aside this tool and instead learn metric prefixes and SI terminology.

Does the history of food energy units suggest a solution to "Calorie confusion"?

An interesting but little known aspect of this situation is that the Calorie predated the joule by more than 60 years, and the original definition was almost exactly the same as presently found on U. One purpose of this article is to explain the priority of the Calorie relative to other energy units, and how it was displaced by the joule and kcal.

  • What's the difference between a calorie and a kilojoule?
  • How to convert joules to calories
  • How to convert joules to calories

A second question that should be addressed is whether there is only one way to do away with the ambiguity imposed by using Calories, g-calories, and kcal in different contexts. This problem has even found its way into U.

How to convert joules to calories (cal)

For example, in Title 21, section More than this, the present impasse was created by very convoluted historical events. Pragmatically, the Calorie is found on food labels because W. Atwater chose the unit to educate the lay public about food energy and also found it practical for compiling tables of food composition. Even though food databases have been updated to express energy as kcal and kJ, food labels have not changed because they are primarily used for education of the lay public, who may only have grade school education.

Therefore, confusion of names for food energy primarily affects nutrition educators in clinical and private practice, rather than scientists who can be expected to understand SI units.

state the relationship between joules and calories

Let us examine how the present situation arose. Definitions of energy units Before discussing the history of the energy units that are commonly used in nutrition, it is useful to provide their present definitions:

state the relationship between joules and calories