Convert 18 km `h^(-1)` into its equivalent in m `s^(-1)`

Explanation

To convert 18 km/h into m/s, we can follow these steps:

### Step 1: Understand the conversion factors
1 kilometer (km) is equal to 1000 meters (m).
1 hour (h) is equal to 3600 seconds (s) because there are 60 minutes in an hour and 60 seconds in a minute (60 minutes × 60 seconds = 3600 seconds).

### Step 2: Set up the conversion
We need to convert 18 km/h to m/s. The conversion can be expressed as:
\[ \text{Speed in m/s} = \text{Speed in km/h} \times \frac{1000 \text{ m}}{1 \text{ km}} \times \frac{1 \text{ h}}{3600 \text{ s}} \]

### Step 3: Substitute the values
Substituting the value of speed:
\[ \text{Speed in m/s} = 18 \text{ km/h} \times \frac{1000 \text{ m}}{1 \text{ km}} \times \frac{1 \text{ h}}{3600 \text{ s}} \]

### Step 4: Perform the calculations
Now, calculate it step by step:
1. Multiply 18 by 1000:
\[ 18 \times 1000 = 18000 \]
2. Now divide by 3600:
\[ \frac{18000}{3600} = 5 \]

### Step 5: Final result
Thus, 18 km/h is equivalent to 5 m/s.

### Summary
The final answer is:
\[ 18 \text{ km/h} = 5 \text{ m/s} \]

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