A car travels a distance of 75 km in 1.5 hours. (i) What is its speed? (ii) Express its speed in m/s. *give answer fast and get branlist
The Correct Answer and Explanation is:
(i) What is its speed in km/h?
To calculate speed:Speed=DistanceTime=75 km1.5 hours=50 km/h\text{Speed} = \frac{\text{Distance}}{\text{Time}} = \frac{75 \, \text{km}}{1.5 \, \text{hours}} = 50 \, \text{km/h}Speed=TimeDistance=1.5hours75km=50km/h
Answer: 50 km/h
(ii) Express its speed in m/s:
To convert from km/h to m/s:1 km/h=10003600=518 m/s1 \, \text{km/h} = \frac{1000}{3600} = \frac{5}{18} \, \text{m/s}1km/h=36001000=185m/s
So,50 km/h×518=25018≈13.89 m/s50 \, \text{km/h} \times \frac{5}{18} = \frac{250}{18} \approx 13.89 \, \text{m/s}50km/h×185=18250≈13.89m/s
Answer: ≈ 13.89 m/s
📘 Textbook-Style Explanation (300 words)
To find how fast an object is moving, the concept of speed is used. Speed tells how much distance is covered in a given time and is mathematically expressed as:Speed=DistanceTime\text{Speed} = \frac{\text{Distance}}{\text{Time}}Speed=TimeDistance
In this problem, a car travels a total distance of 75 kilometers in 1.5 hours. Applying the formula:Speed=75 km1.5 h=50 km/h\text{Speed} = \frac{75 \, \text{km}}{1.5 \, \text{h}} = 50 \, \text{km/h}Speed=1.5h75km=50km/h
This means the car covers 50 kilometers every hour.
To express speed in meters per second (m/s), a unit commonly used in scientific contexts, a conversion is required. There are 1000 meters in one kilometer and 3600 seconds in one hour. So:1 km/h=1000 m3600 s=518 m/s1 \, \text{km/h} = \frac{1000 \, \text{m}}{3600 \, \text{s}} = \frac{5}{18} \, \text{m/s}1km/h=3600s1000m=185m/s
Multiplying the speed in km/h by this factor gives:50 km/h×518=25018≈13.89 m/s50 \, \text{km/h} \times \frac{5}{18} = \frac{250}{18} \approx 13.89 \, \text{m/s}50km/h×185=18250≈13.89m/s
Therefore, the car’s speed is 50 kilometers per hour or approximately 13.89 meters per second. Expressing speed in m/s is useful when analyzing motion in physics, especially when dealing with acceleration, force, or kinetic energy, because these calculations use SI units.
