Calculating Energy Absorption by an Iron Park Bench

The absorption of heat energy by an object is a fundamental concept in thermodynamics, often encountered in real-world applications such as the temperature changes in park benches exposed to the sun. For example, a 144 kg iron park bench experiences a temperature increase from 25°C to 35°C. This article will explore the calculation of the energy absorbed by the bench using the specific heat capacity of iron, and discuss the concept in practical terms.

Introduction to Heat Energy and Specific Heat Capacity

Heat energy is the form of energy that flows from one substance to another due to a temperature difference. It can be quantified using the formula Q mcΔT, where:

Q is the heat energy absorbed (or released) in joules (J). m is the mass of the object in kilograms (kg). c is the specific heat capacity of the material in joules per kilogram Kelvin (J/kg·K). ΔT is the change in temperature in degrees Celsius (°C) or Kelvin (K).

Problem Statement

The specific heat of iron at 25°C is 449 J/kg·K. A 144 kg park bench made of iron is exposed to the sun and its temperature increases from 25°C to 35°C. To find the amount of energy absorbed by the park bench, we need to plug the given values into the formula:

Calculations and Understanding

Given Values:

Mass (m): 144 kg Specific heat capacity (c): 449 J/kg·K Initial temperature (Ti): 25°C 298K Final temperature (Tf): 35°C 308K

The change in temperature (ΔT) is calculated as:

ΔT Tf - Ti 35°C - 25°C 10°C 10K

Using the formula for heat energy:

Q m · c · ΔT

Substituting the values:

Q 144 kg · 449 J/kg·K · 10 K

Q 144 · 4490 J 646560 J

To convert joules to kilojoules, we divide by 1000:

Q 646560 J / 1000 646.56 kJ

Conclusion: The park bench absorbs approximately 646.56 kJ of energy.

Alternative Calculations

For a different approach, if we consider the specific heat capacity in kJ/kg-K (0.449 kJ/kg-K), the calculation becomes:

Q 144 kg · 0.449 kJ/kg-K · 10 K

Q 144 · 4.49 kJ 646.56 kJ

Practical Applications and Real-World Implications

Understanding how energy is absorbed by materials in different temperature conditions is crucial for various applications, including environmental engineering, thermal analysis, and materials science. The energy absorbed by the park bench could affect its durability and comfort, influencing the choice of materials in park furniture design.

Conclusion

This article has provided a step-by-step guide to calculating the energy absorbed by an iron park bench using specific heat capacity and temperature change. The practicality of such calculations is instrumental in ensuring that materials used in outdoor equipment can withstand temperature variations, making the environment more comfortable for users.