Examkin

Question

Difficulty: MediumHeat Capacity and Insulation

Two metal brackets of equal mass are exposed to 500 Joules of thermal energy. Bracket A has a specific heat capacity that is exactly twice as large as that of Bracket B. If both brackets start at 20°C, which of the following statements correctly describes the outcome of this energy absorption?

  1. Bracket B will experience a temperature increase twice as large as Bracket A.Answer
  2. B
    Bracket A will experience a temperature increase twice as large as Bracket B.
  3. C
    Both brackets will experience the exact same temperature increase since they absorbed equal energy.
  4. D
    Bracket B will shrink in size because materials with lower heat capacity contract when absorbing energy.

Answer

Bracket B will experience a temperature increase twice as large as Bracket A.
Specific heat capacity measures how much energy is needed to raise the temperature of a substance. Because Bracket A has twice the specific heat capacity of Bracket B, it requires twice as much energy to heat up by the same amount. Since both brackets receive the exact same amount of thermal energy (500 Joules) and have equal masses, Bracket B—with its lower resistance to temperature change—will experience a temperature increase that is twice as large as that of Bracket A.

Step-by-Step Solution

1
Identify the relationship between specific heat capacity and temperature change.
Temperature change is inversely proportional to specific heat capacity when mass and added heat are constant.
The formula for heat energy is Q=mcΔTQ = mc\Delta T. Rearranging for temperature change gives ΔT=Qmc\Delta T = \frac{Q}{mc}.
2
Compare the specific heat capacities of the two brackets.
Bracket A has twice the specific heat capacity (cc) of Bracket B.
This is stated directly in the problem.
3
Determine the resulting temperature changes.
Since Bracket B has half the specific heat capacity of A, its temperature change (ΔT\Delta T) will be twice as large.
A smaller denominator in the formula ΔT=Qmc\Delta T = \frac{Q}{mc} results in a larger overall temperature change.

Key Concept

The specific heat capacity of a material determines how much thermal energy is required to change its temperature; materials with lower specific heat capacities will experience greater temperature changes for a given amount of heat input.
Estimated Time:1m 0s
Rate this question

Topics

Heat Capacity and Insulation

More questions from this topic