Specific heat capacity of substance A is 3.8 J/gK, whereas the specific heat capacity of substance B is 0.4 J/gK
Which of the two is good conductor of heat ?

Explanation

To determine which substance is a good conductor of heat based on their specific heat capacities, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Specific Heat Capacity**: Specific heat capacity (c) is the amount of heat required to raise the temperature of 1 gram of a substance by 1 Kelvin (or 1 degree Celsius). The lower the specific heat capacity, the less heat is required to change the temperature of the substance.

2. **Identify the Given Values**:
- Specific heat capacity of substance A (c_A) = 3.8 J/gK
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