To solve this problem, we can break it down into three parts:
Part 1: The motorist drives north for 35.0 minutes at 85.0 km/h.
The distance covered in this part can be calculated using the formula:
Distance = speed × time
= 85.0 km/h × (35.0 minutes / 60.0 minutes per hour)
= 85.0 km/h × 0.583 hours
= 49.455 km
Since the motorist is driving north, the displacement in this part is also 49.455 km north.
Part 2: The motorist stops for 15.0 minutes. During this time, there is no displacement because he is not moving.
Part 3: The motorist continues north and travels 130 km in 2.00 hours.
The displacement in this part is also 130 km north.
Now, let's calculate the total displacement:
Total displacement = Displacement in Part 1 + Displacement in Part 2 + Displacement in Part 3
= 49.455 km + 0 km + 130 km
= 179.455 km
The total displacement is 179.455 km.
To calculate the average velocity, we use the formula:
Average velocity = Total displacement / Total time
The total time is the sum of the times in all three parts:
Total time = Time in Part 1 + Time in Part 2 + Time in Part 3
= 35.0 minutes + 15.0 minutes + 2.00 hours
= 35.0 minutes + 15.0 minutes + 120 minutes
= 170 minutes
Converting the total time to hours:
Total time = 170 minutes / 60.0 minutes per hour
= 2.833 hours
Now we can calculate the average velocity:
Average velocity = Total displacement / Total time
= 179.455 km / 2.833 hours
= 63.296 km/h
The average velocity is 63.296 km/h.
A motorist drives north for 35.0 minutes at 85.0 km/h and then stops for 15.0 minutes. He then continues north traveling 130 km in 2.00 h. What is his total displacement? What is his average velocity?
1 answer