Question

СРОЧНО!! ДАЮ 90 БАЛОВ!! Щоб витягти вантаж вгору по похилій площині з кутом нахилу 15 °, треба докласти силу 120 Н, а щоб стягнути вниз, треба прикласти силу 15 Н. Знайдіть коефіцієнт тертя вантажу об площину, якщо в обох випадках сила спрямована вздовж похилій. ​

Answer 1

Ответ:  0,34

Объяснение: Див. додаток

Answer 2

To find the coefficient of friction between the load and the inclined plane, we can use the formula:

Coefficient of friction (μ) = Force of friction (Ff) / Normal force (Fn)

In this case, the force of friction is equal to the force applied to move the load up or down the inclined plane. The normal force is the component of the weight of the load perpendicular to the inclined plane.

Calculating the coefficient of friction when pulling the load up the inclined plane:

The force applied to move the load up the inclined plane is 120 N. The angle of inclination is 15°.

To calculate the normal force, we need to find the component of the weight of the load perpendicular to the inclined plane. The weight of the load can be calculated using the formula:

Weight (W) = mass (m) * gravitational acceleration (g)

Let's assume the mass of the load is 1 kg. The gravitational acceleration is approximately 9.8 m/s².

Weight (W) = 1 kg * 9.8 m/s² = 9.8 N

The normal force (Fn) is the component of the weight perpendicular to the inclined plane, which can be calculated using the formula:

Fn = Weight (W) * cos(angle of inclination)

Fn = 9.8 N * cos(15°) ≈ 9.37 N

Now, we can calculate the coefficient of friction (μ) using the formula mentioned earlier:

Coefficient of friction (μ) = Force of friction (Ff) / Normal force (Fn)

Coefficient of friction (μ) = 120 N / 9.37 N ≈ 12.81

Therefore, the coefficient of friction between the load and the inclined plane when pulling it up is approximately 12.81.

Calculating the coefficient of friction when pulling the load down the inclined plane:

The force applied to move the load down the inclined plane is 15 N. The angle of inclination is 15°.

Using the same calculations as before, we find that the normal force (Fn) is approximately 9.37 N.

Now, we can calculate the coefficient of friction (μ) using the formula mentioned earlier:

Coefficient of friction (μ) = Force of friction (Ff) / Normal force (Fn)

Coefficient of friction (μ) = 15 N / 9.37 N ≈ 1.60

Therefore, the coefficient of friction between the load and the inclined plane when pulling it down is approximately 1.60.

Please note that these calculations assume that the load is not accelerating and that the coefficient of friction remains constant throughout the motion.