Solar constant at height at 83 km in

Options

A. `"1 kcal/cm"^(2)//"min"`
B. `"1 cal/cm"^(2)//"min"`
C. `"2 kcal/cm"^(2)//"min"`
D. `"2 cal/cm"^(2)//"min"`

Answer

To solve the question regarding the solar constant at a height of 83 km, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Solar Constant**:
- The solar constant refers to the average amount of solar energy received per unit area at the outer surface of the Earth's atmosphere. It is measured in calories per square centimeter per minute.

2. **Identify the Given Height**:
- The question specifies a height of 83 km. This is within the Earth's atmosphere, where the solar constant is typically measured.

3. **Recall the Value of Solar Constant**:
- The solar constant is approximately 2 calories per square centimeter per minute at the upper atmosphere. This value is consistent regardless of slight variations in altitude within the atmosphere.

4. **Evaluate the Options Provided**:
- The options given are:
1. 1 kilocalorie per centimeter square per minute
2. 1 calorie per centimeter square per minute
3. 2 kilocalories per centimeter square per minute
4. 2 calories per centimeter square per minute
- Based on the known value of the solar constant, we can eliminate the first three options.

5. **Select the Correct Answer**:
- The only option that matches the known value of the solar constant at the specified height is:
- **2 calories per centimeter square per minute**.

### Final Answer:
The solar constant at a height of 83 km is **2 calories per centimeter square per minute**.

---