Question

Диаметр колеса автомобиля равен 0,75 метра. найдите скорость этого автомобиля в тот момент, когда его колесо совершает 14 полных оборотов за одну секунду. ответ выразите в км/ч, округлив до целого числа.

Answer 1

1)С=2пr=0.75×3.14=2.355
2)14×2.355=32.97(м.)-расстояние за 14 секунд
3)2.355 м/с=8.478=8 км/ч
Ответ: 8 км/ч

Answer 2

Calculation of the Speed of the Car

To calculate the speed of the car when its wheel completes 14 full revolutions per second, we can use the formula:

Speed = Circumference of the Wheel × Number of Revolutions per Second

The diameter of the wheel is given as 0.75 meters. To find the circumference of the wheel, we can use the formula:

Circumference = π × Diameter

where π is a mathematical constant approximately equal to 3.14159.

Let's calculate the speed of the car using these formulas.

Calculation Steps:

1. Calculate the circumference of the wheel: - Diameter = 0.75 meters - Circumference = π × Diameter

2. Calculate the speed of the car: - Number of Revolutions per Second = 14 - Speed = Circumference × Number of Revolutions per Second

Let's perform the calculations:

1. Calculate the circumference of the wheel: - Diameter = 0.75 meters - Circumference = π × Diameter

Using the value of π as approximately 3.14159: - Circumference = 3.14159 × 0.75 meters

The circumference of the wheel is approximately 2.35619 meters.

2. Calculate the speed of the car: - Number of Revolutions per Second = 14 - Speed = Circumference × Number of Revolutions per Second

Substituting the values: - Speed = 2.35619 meters × 14 revolutions per second

The speed of the car is approximately 32.98666 meters per second.

To convert the speed from meters per second to kilometers per hour, we can use the conversion factor: - 1 kilometer = 1000 meters - 1 hour = 3600 seconds

Let's convert the speed to kilometers per hour:

- Speed in kilometers per hour = (Speed in meters per second × 3600) / 1000

Substituting the value of the speed in meters per second: - Speed in kilometers per hour = (32.98666 meters per second × 3600) / 1000

The speed of the car, when its wheel completes 14 full revolutions per second, is approximately 118.752 kilometers per hour (rounded to the nearest whole number).

Please note that the above calculations are based on the given information and assumptions.