One atmosphere is equal to

Options

A. 760 cm
B. `10^(5) Nm^(-2)`
C. `10^(4)` dynes `cm^(-2)`
D. 10 Bar

Explanation

To solve the question "One atmosphere is equal to", we need to identify the equivalent values of one atmosphere in different units of pressure. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Definition of Atmosphere
One atmosphere (atm) is a unit of pressure defined as being precisely equal to the average atmospheric pressure at sea level.

### Step 2: Convert Atmosphere to Bar
1 atm is equal to 1.013 bar.
- This means that 1 atm is slightly more than 1 bar.

### Step 3: Convert Atmosphere to mm of Hg
1 atm is also equal to 760 mm of Hg (millimeters of mercury).
- This conversion is based on the height of a mercury column that can be supported by atmospheric pressure.

### Step 4: Convert Atmosphere to dynes/cm²
1 atm is equal to 1.013 × 10^6 dynes/cm².
- This is a unit of pressure in the CGS (centimeter-gram-second) system.

### Step 5: Convert Atmosphere to Newton/m²
1 atm is equal to 1.013 × 10^5 N/m² (newtons per square meter).
- This is the SI unit of pressure, also known as Pascal (Pa).

### Conclusion
Thus, one atmosphere can be expressed in several units:
- 1 atm = 1.013 bar
- 1 atm = 760 mm of Hg
- 1 atm = 1.013 × 10^6 dynes/cm²
- 1 atm = 1.013 × 10^5 N/m²

### Final Answer
One atmosphere is equal to 1.013 × 10^5 N/m².

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