Question

Автомобиль массой m=5т равномерно со скоростью V=72км/ч съезжает в вогнутый мост,представляющий собой дугу окружности радиусом R=80м .Определить,с какой силой автомобиль давит на мост в точке,радиус которой составляет с радиусом впадины моста угол альфа=30

Answer 1

Скорость переведи в м/c.
F=ma

Answer 2

Problem Statement

We have a car with a mass of 5 tons (m = 5,000 kg) moving at a constant speed of 72 km/h (V = 72 km/h). The car is descending into a concave bridge, which is represented by a circular arc with a radius of 80 meters (R = 80 m). We need to determine the force with which the car presses against the bridge at a point where the radius forms an angle of 30 degrees (α = 30 degrees) with the radius of the bridge's concavity.

Solution

To find the force with which the car presses against the bridge, we need to consider the centripetal force acting on the car as it moves along the curved path of the bridge. The centripetal force is the force that keeps an object moving in a circular path and is directed towards the center of the circle.

The centripetal force can be calculated using the following formula:

F = (m * V^2) / R

Where: - F is the centripetal force - m is the mass of the car - V is the velocity of the car - R is the radius of the circular path

Let's calculate the centripetal force using the given values.

Given: - m = 5,000 kg - V = 72 km/h = 20 m/s (since 1 km/h = 1000 m/3600 s) - R = 80 m

Substituting the values into the formula, we get:

F = (5,000 kg * (20 m/s)^2) / 80 m

Simplifying the equation, we have:

F = (5,000 kg * 400 m^2/s^2) / 80 m

F = 25,000 N

Therefore, the force with which the car presses against the bridge at the point where the radius forms an angle of 30 degrees is 25,000 Newtons.

Conclusion

The car exerts a force of 25,000 Newtons on the bridge at the point where the radius forms an angle of 30 degrees with the radius of the bridge's concavity.