Question

4. Автомобіль перших 5 км їхав зі швидкістю 90 км/год, а потім ще 3000 м зі швидкістю 900 м/хв.. Яка середня Швидкість?

Answer 1

Ответ:

Vсер=20 м/c=72 км/год

Объяснение:

S=5000+3000=8000 м

t=t₁+t₂=5/90*3600+3000/900*60=200+200=400 c

Vсер=S/t=8000/400=20 м/c= 20*3600/1000=72 км/год

Answer 2

Calculation of Average Speed

To calculate the average speed, we need to find the total distance traveled and the total time taken.

The car first traveled 5 km at a speed of 90 km/h. This means it took 5 km / 90 km/h = 0.0556 hours to cover this distance.

Then, the car traveled an additional 3000 m at a speed of 900 m/min. To convert the speed to km/h, we need to multiply it by 60 (since there are 60 minutes in an hour) and then divide by 1000 (to convert meters to kilometers). So, the speed is (900 m/min * 60 min/h) / 1000 = 54 km/h.

To find the time taken to cover the additional distance, we need to convert the distance to kilometers. Since 1 km = 1000 m, the additional distance is 3000 m / 1000 = 3 km. Therefore, it took 3 km / 54 km/h = 0.0556 hours to cover this distance.

Now, we can calculate the total distance and total time taken:

Total distance = 5 km + 3 km = 8 km Total time = 0.0556 hours + 0.0556 hours = 0.1112 hours

Finally, we can calculate the average speed by dividing the total distance by the total time:

Average speed = Total distance / Total time = 8 km / 0.1112 hours ≈ 71.92 km/h.

Therefore, the average speed of the car for the entire journey is approximately 71.92 km/h.