To convert the speed from kilometers per hour (km/hr) to meters per second (m/s), we need to use the following conversion factors:
1 kilometer = 1000 meters 1 hour = 3600 seconds
First, let's calculate the distance traveled in meters:
Distance = Speed × Time
Distance = 20 km/hr × 2 hours Distance = 40 km
Next, we'll convert the distance from kilometers to meters:
Distance = 40 km × 1000 meters/kilometer Distance = 40,000 meters
Finally, we'll calculate the speed in m/s:
Speed = Distance / Time
Speed = 40,000 meters / 2 hours Speed = 20,000 meters/hour
Now, we'll convert from meters per hour to meters per second:
Speed = 20,000 meters/hour × 1 hour / 3600 seconds Speed ≈ 5.56 m/s (rounded to two decimal places)
Therefore, the girl's speed is approximately 5.56 m/s.