The energy required to raise water by 1°F is called 1 Btu.

The energy required to raise water by 1°F is called 1 Btu.

• A. 1 calorie
• B. 1 joule
• C. 1 Btu
• D. 1 watt-hour

Answer: (C)

Heat energy for liquids is often discussed in terms of how much energy it takes to raise a given mass by a specific temperature change. One BTU is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. That direct link between mass (one pound) and a small temperature rise (one °F) is why this unit is used in heating and HVAC contexts. In numbers, 1 BTU is about 1055 joules, roughly 252 calories. By comparison, a calorie is defined for raising 1 gram of water by 1°C, a joule is a general energy unit that’s smaller than a BTU, and a watt-hour is energy for consuming one watt for an hour (3600 J). So the term that exactly matches the described energy for water is 1 BTU.

Heat energy for liquids is often discussed in terms of how much energy it takes to raise a given mass by a specific temperature change. One BTU is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. That direct link between mass (one pound) and a small temperature rise (one °F) is why this unit is used in heating and HVAC contexts. In numbers, 1 BTU is about 1055 joules, roughly 252 calories. By comparison, a calorie is defined for raising 1 gram of water by 1°C, a joule is a general energy unit that’s smaller than a BTU, and a watt-hour is energy for consuming one watt for an hour (3600 J). So the term that exactly matches the described energy for water is 1 BTU.