Question

Материальное тело массой 5 кг скользит по наклонной плоскости (угол наклона плоскости 30°) из состояния покоя. Через 10 сек после начала движения тело имело скорость 10м/сек. Определить силу трения при скольжении тела.

Answer 1

Ответ: Сила трения равна Fтр=20(Н).

Answer 2

Problem Analysis

We are given the following information: - A body with a mass of 5 kg is sliding down a inclined plane with an angle of 30°. - The body starts from rest and after 10 seconds, it has a velocity of 10 m/s. - We need to determine the force of friction acting on the body during its sliding motion.

To solve this problem, we can use the equations of motion and the concept of forces to find the force of friction.

Solution

Let's break down the problem into steps:

Step 1: Find the acceleration of the body. We can use the equation of motion: v = u + at, where: - v is the final velocity (10 m/s), - u is the initial velocity (0 m/s, as the body starts from rest), - a is the acceleration, and - t is the time (10 seconds).

Using the equation, we can solve for the acceleration: 10 = 0 + a * 10 a = 10/10 a = 1 m/s²

Step 2: Find the force of gravity acting on the body. The force of gravity can be calculated using the equation: F = m * g, where: - F is the force of gravity, - m is the mass of the body (5 kg), and - g is the acceleration due to gravity (approximately 9.8 m/s²).

Substituting the values, we get: F = 5 * 9.8 F = 49 N

Step 3: Find the component of the force of gravity along the inclined plane. The component of the force of gravity acting along the inclined plane can be calculated using the equation: F_parallel = F * sin(θ), where: - F_parallel is the component of the force of gravity along the inclined plane, - F is the force of gravity (49 N), and - θ is the angle of the inclined plane (30°).

Substituting the values, we get: F_parallel = 49 * sin(30°) F_parallel ≈ 24.5 N

Step 4: Find the force of friction. The force of friction can be calculated using the equation: F_friction = μ * F_normal, where: - F_friction is the force of friction, - μ is the coefficient of friction, and - F_normal is the normal force.

To find the normal force, we can use the equation: F_normal = F * cos(θ), where: - F_normal is the normal force, - F is the force of gravity (49 N), and - θ is the angle of the inclined plane (30°).

Substituting the values, we get: F_normal = 49 * cos(30°) F_normal ≈ 42.4 N

Now, we can substitute the values of F_normal and F_friction into the equation to find the force of friction: F_friction = μ * F_normal

However, we don't have the coefficient of friction (μ) given in the problem statement or the search results. Without this information, we cannot calculate the exact value of the force of friction.

Please provide the coefficient of friction (μ) so that we can proceed with the calculation.