a car travels at 20km/h for 1.5h, at 30km/h for 2.0h, and at 40kmh for 0.75 h. What is the car average velocity
d1 = 20 * 1.5 = 30km.
d2 = 30 * 2 = 60km.
d3 = 40 * 0.75 = 30km.
Vavg. = (d1+d2+d3) / (t1+t2+t3),
Vavg. = 120 / 4.25 = 28.2km/h.
To find the average velocity, we need to find the total distance traveled and divide it by the total time taken.
Step 1: Calculate the distance traveled at each speed.
Distance 1 = Speed 1 × Time 1 = 20 km/h × 1.5 h = 30 km
Distance 2 = Speed 2 × Time 2 = 30 km/h × 2.0 h = 60 km
Distance 3 = Speed 3 × Time 3 = 40 km/h × 0.75 h = 30 km
Step 2: Calculate the total distance.
Total Distance = Distance 1 + Distance 2 + Distance 3 = 30 km + 60 km + 30 km = 120 km
Step 3: Calculate the total time.
Total Time = Time 1 + Time 2 + Time 3 = 1.5 h + 2.0 h + 0.75 h = 4.25 h
Step 4: Calculate the average velocity.
Average Velocity = Total Distance / Total Time = 120 km / 4.25 h = 28.24 km/h (rounded to two decimal places)
Therefore, the average velocity of the car is approximately 28.24 km/h.
To find the average velocity of the car, we need to calculate the total distance traveled by the car and divide it by the total time it took.
First, let's calculate the distance traveled at each speed:
Distance traveled at 20 km/h = Speed × Time = 20 km/h × 1.5 h = 30 km
Distance traveled at 30 km/h = Speed × Time = 30 km/h × 2.0 h = 60 km
Distance traveled at 40 km/h = Speed × Time = 40 km/h × 0.75 h = 30 km
Now, let's calculate the total distance traveled by adding up the three distances:
Total distance = 30 km + 60 km + 30 km = 120 km
Next, let's calculate the total time taken:
Total time = 1.5 h + 2.0 h + 0.75 h = 4.25 h
Finally, we can calculate the average velocity by dividing the total distance by the total time:
Average velocity = Total distance ÷ Total time = 120 km ÷ 4.25 h ≈ 28.24 km/h
Therefore, the car's average velocity is approximately 28.24 km/h.