Heat And Specific Heat Capacity Flashcards
(25 cards)
What is heat?
Heat is the transfer of thermal energy from one object to another because of a difference in temperature.
In what unit is heat measured?
Heat is measured in joules (J).
What are the three modes of heat transfer?
Conduction, convection, and radiation.
Define specific heat capacity.
Specific heat capacity is the amount of heat required to raise the temperature of 1 kg of a substance by 1°C (or 1 K).
What is the formula for calculating specific heat capacity?
c = \frac{Q}{m \Delta T}
= Heat energy (J)
= Mass (kg)
= Specific heat capacity (J/kg°C)
= Temperature change (°C or K)
What does the term ΔT represent in the formula for heat energy?
ΔT represents the change in temperature, calculated as:
ΔT = T_2 - T_1
Why does water have a high specific heat capacity?
Water requires a lot of energy to change its temperature, making it an excellent heat regulator.
Why does metal heat up faster than water?
Metals have low specific heat capacities, so they require less energy to change their temperature.
How does specific heat capacity affect coastal climates?
Water’s high specific heat capacity moderates temperature changes, keeping coastal areas cooler during the day and warmer at night.
Why do deserts have extreme temperature changes between day and night?
Sand has a low specific heat capacity, so it heats up and cools down quickly.
What role does specific heat capacity play in car radiators?
Coolants with high specific heat absorb more heat, keeping engines from overheating.
Why does water take longer to boil compared to cooking oil?
Water has a higher specific heat capacity than oil, requiring more energy to increase its temperature.
How does the human body use specific heat capacity to regulate temperature?
The body’s water content absorbs and retains heat efficiently, helping to maintain a stable temperature.
What is a calorimeter used for?
A calorimeter measures the specific heat capacity of substances by determining the heat transferred.
State the principle of conservation of energy in heat transfer.
Heat lost by the hotter substance equals heat gained by the cooler substance.
Why does a metal spoon feel hotter than a wooden spoon in hot soup?
Metal has a lower specific heat capacity and conducts heat faster than wood.
Why are coastal areas warmer at night?
Water retains heat longer due to its high specific heat capacity, releasing it slowly at night.
What precautions should be taken when determining specific heat capacity experimentally?
Insulate the system to prevent heat loss.
Accurately measure time and temperature.
Avoid overheating the substance.
What is the specific heat capacity of water?
Approximately 4.18 J/g°C.
What is thermal equilibrium?
Thermal equilibrium occurs when two substances in contact reach the same temperature, with no net heat flow.
How does specific heat capacity influence fire extinguishers?
Water is used because its high specific heat capacity absorbs a lot of heat, cooling the fire effectively.
How does the formula for heat energy relate to real-life applications?
The formula: Q = mcΔT
What is the significance of specific heat capacity in engineering?
Engineers design cooling and heating systems, like air conditioners and refrigerators, based on specific heat capacities of materials.
Why does it take longer to heat a large pot of water compared to a small one?
The larger pot has more mass, requiring more heat energy to raise its temperature.
