Which of the following represents the highest pressure?

Options

A. One atmosphere
B. Five pounds per square inch
C. One mm of Hg
D. One hundred Pascal

Explanation

To determine which of the given options represents the highest pressure, we will analyze each option step by step.

### Step 1: Understand the concept of pressure
Pressure is defined as the force exerted per unit area. The formula for pressure (P) is given by:
\[ P = \frac{F}{A} \]
where \( F \) is the force and \( A \) is the area.

### Step 2: Analyze the given options
We have the following options for pressure:
1. 1 atmosphere (atm)
2. 5 pounds per square inch (psi)
3. 1 mm of Hg
4. 100 Pascal (Pa)

### Step 3: Convert all options to a common unit
To compare the pressures effectively, we should convert all options to the same unit. We will convert them to Pascals (Pa).

1. **1 atm to Pascals**:
\[ 1 \text{ atm} = 1.01 \times 10^5 \text{ Pa} \]

2. **5 psi to Pascals**:
\[ 1 \text{ psi} = 6894.76 \text{ Pa} \]
Therefore,
\[ 5 \text{ psi} = 5 \times 6894.76 \text{ Pa} = 34473.8 \text{ Pa} \]

3. **1 mm of Hg to Pascals**:
\[ 1 \text{ mm of Hg} = 133.322 \text{ Pa} \]

4. **100 Pa** is already in Pascals.

### Step 4: Compare the values
Now we have:
- 1 atm = \( 1.01 \times 10^5 \) Pa = 101000 Pa
- 5 psi = 34473.8 Pa
- 1 mm of Hg = 133.322 Pa
- 100 Pa = 100 Pa

### Step 5: Identify the highest pressure
From the values calculated:
- 1 atm = 101000 Pa
- 5 psi = 34473.8 Pa
- 1 mm of Hg = 133.322 Pa
- 100 Pa = 100 Pa

The highest pressure among these options is **1 atmosphere (1 atm)**.

### Conclusion
Thus, the option that represents the highest pressure is **1 atmosphere (atm)**.

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