The surface tension of water is 72 dyne//cm. convert it inSI unit.

Explanation

To convert the surface tension of water from CGS units (dyne/cm) to SI units (N/m), we can follow these steps:

### Step 1: Understand the given value
The surface tension of water is given as 72 dyne/cm.

### Step 2: Convert dynes to newtons
We know that:
1 Newton (N) = 10^5 dynes

To convert 72 dynes to newtons, we use the conversion factor:
\[ \text{Surface tension in N} = \frac{72 \text{ dyne}}{10^5 \text{ dyne/N}} = 72 \times 10^{-5} \text{ N} \]

### Step 3: Convert centimeters to meters
We also know that:
1 cm = 0.01 m = 10^{-2} m

### Step 4: Combine the conversions
Now, we need to convert the surface tension from dyne/cm to N/m. We can do this by dividing the value in newtons by the value in meters:
\[ \text{Surface tension in N/m} = \frac{72 \times 10^{-5} \text{ N}}{10^{-2} \text{ m}} \]

### Step 5: Simplify the expression
This simplifies to:
\[ \text{Surface tension in N/m} = 72 \times 10^{-5} \times 10^{2} \text{ N/m} = 72 \times 10^{-3} \text{ N/m} \]

### Step 6: Final result
Thus, the surface tension of water in SI units is:
\[ \text{Surface tension} = 0.072 \text{ N/m} \]

### Summary
The surface tension of water, originally given as 72 dyne/cm, converts to 0.072 N/m in SI units.

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