Convert each of the following speeds into m/sec :
90km/hr

Answer

To convert the speed from kilometers per hour (km/hr) to meters per second (m/sec), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the conversion factors**:
- 1 kilometer (km) = 1000 meters (m)
- 1 hour (hr) = 3600 seconds (sec)

2. **Set up the conversion**:
- We have a speed of 90 km/hr.
- We want to convert this into m/sec.

3. **Write the conversion formula**:
\[ \text{Speed in m/sec} = \text{Speed in km/hr} \times \frac{1000 \text{ m}}{1 \text{ km}} \times \frac{1 \text{ hr}}{3600 \text{ sec}} \]

4. **Substitute the values**:
\[ \text{Speed in m/sec} = 90 \times \frac{1000}{3600} \]

5. **Simplify the fraction**:
- First, simplify \( \frac{1000}{3600} \):
\[ \frac{1000}{3600} = \frac{10}{36} = \frac{5}{18} \]
- Now, substitute back into the equation:
\[ \text{Speed in m/sec} = 90 \times \frac{5}{18} \]

6. **Calculate the final speed**:
- Perform the multiplication:
\[ \text{Speed in m/sec} = \frac{90 \times 5}{18} = \frac{450}{18} = 25 \]

7. **Final result**:
- Therefore, 90 km/hr is equal to 25 m/sec.

### Final Answer:
90 km/hr = 25 m/sec

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