Question

60 БАЛЛОВ! Тело начинает тормозить, имея скорость V0 20, при торможении тело проходит расстояние S за время t 3с. Масса тела m?, коэф. трения h?, сила трения Fтр. 6700 Н, ускорение тела a 6,7 м/c^2

Answer 1

Vo=20 м/с    t=3 c    F=6700 H    a=-6.7 м/с²   s=?   m=?   h=?
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F=m*a     m=F/a=6700/6.7=1000 кг
А=h*m*g     h=F/(m*g)=6700/(1000*10)=0.67
s=vo*t+at²/2=20*6-6.7*9/2≈30 м   (при торможении ускорение отрицательное)
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Answer 2

Calculation of Mass and Friction Coefficient

To calculate the mass of the body and the friction coefficient, we can use the given information about the initial velocity, braking distance, time, friction force, and acceleration.

Let's break down the problem and use the relevant formulas:

1. The body starts with an initial velocity V0 of 20 m/s. 2. The body comes to a stop in a time t of 3 seconds. 3. The body covers a distance S during this time. 4. The friction force Fтр acting on the body is given as 6700 N. 5. The acceleration a of the body is 6.7 m/s^2.

We can use the following formulas to solve for the mass m and the friction coefficient h:

1. The equation of motion for constant acceleration is: S = V0 * t + (1/2) * a * t^2. 2. The friction force is given by: Fтр = m * g * h, where g is the acceleration due to gravity (approximately 9.8 m/s^2).

To find the mass m, we can rearrange the equation for friction force as follows:

m = Fтр / (g * h)

Let's substitute the given values into the equations and calculate the mass and friction coefficient.

Using the equation of motion, we can find the distance S:

S = V0 * t + (1/2) * a * t^2

Substituting the values:

S = 20 * 3 + (1/2) * 6.7 * 3^2

Simplifying the equation:

S = 60 + 30.15

S = 90.15 meters

Now, let's calculate the mass m:

m = Fтр / (g * h)

Substituting the given values:

m = 6700 / (9.8 * h)

To find the friction coefficient h, we need more information or an additional equation. Unfortunately, the given information does not provide enough details to calculate the friction coefficient.

Therefore, we can calculate the mass m using the given values, but we cannot determine the friction coefficient h without additional information.

Please note that the calculations provided are based on the given information and assumptions. If there are any additional details or constraints, please let me know, and I will be happy to assist you further.