cold
Definition
Cold is a relative term that refers to a temperature below the human body's normal temperature of 37 degrees Celsius (98.6 degrees Fahrenheit).
Cold can be caused by a variety of factors, including low air temperature, exposure to cold water, and certain medical conditions.
When the body is exposed to cold, it undergoes a series of physiological changes in order to conserve heat. These changes include shivering, increased heart rate, and decreased blood flow to the extremities.
If the body is unable to maintain its temperature, hypothermia can occur. Hypothermia is a medical emergency that can be fatal if not treated.
How can the word be used?
The temperature outside is cold.
Different forms of the word
Adjective:
Cold: having a relatively low temperature.
Cold-blooded: having a body temperature that changes with the temperature of the environment.
Cold-hearted: unfeeling or unsympathetic.
Cold-pressed: made by pressing something without using heat.
Noun:
Cold: a state of being cold.
Common cold: a mild viral infection of the upper respiratory tract.
Cold snap: a period of unusually cold weather.
Cold storage: a place where food is stored at a low temperature.
Verb:
To cold: to make something cold.
To cold-shoulder: to ignore or treat someone with indifference.
Etymology
The word "cold" comes from the Old English word "cald", which also means "cold". The Old English word "cald" is thought to come from the Proto-Germanic word kaldaz, which also means "cold".
Question
What happens outside when the weather is cold?
AQA Science Exam Question and Answer
Question:
Explain the concept of "cold" in the context of temperature and the transfer of thermal energy, and discuss how objects lose heat to their surroundings in colder environments.
Answer:
In science, "cold" refers to a low-temperature state of an object or substance. Temperature is a measure of the average kinetic energy of particles in a material. When the average kinetic energy decreases, the temperature is considered cold.
The transfer of thermal energy occurs from objects at higher temperatures to those at lower temperatures. In colder environments, objects lose heat to their surroundings through various mechanisms. One primary method is conduction, where heat is transferred from a warmer object to a cooler one through direct contact. Another mechanism is radiation, where heat energy is emitted in the form of electromagnetic waves. For example, a person standing outside on a cold day loses heat through radiation to the cooler air.
Furthermore, objects can also lose heat through convection, particularly in fluids like air or water. In convection, warmer, less dense regions rise while cooler, denser regions sink, creating a continuous flow of heat transfer.
Overall, "cold" is a relative term describing lower temperatures, and understanding the mechanisms of heat transfer is essential to comprehend how objects lose heat to their surroundings in colder environments.