Question

Коэффициент трения скольжения ящика массой 100кг о пол равен 0,2. Ящик тянут за веревку с горизонтальной силой равной 300Н. Определите, С каким ускорением движется ящик и какова при этом сила трения скольжения ящика о пол

Answer 1

F-Fтр=ma
N-mg=0
N=mg
Fтр=kN=kmg
Fтр=0.2*100*9.8=196Н
a=(F-Fтр)/m
a=(300-196)/100=1.04м/с^2

Answer 2

Calculation of Acceleration and Frictional Force

To determine the acceleration and frictional force of the box, we can use the given information. The box has a mass of 100 kg and is being pulled horizontally with a force of 300 N. The coefficient of sliding friction between the box and the floor is 0.2.

First, let's calculate the force of friction using the formula:

Frictional force (Ff) = coefficient of sliding friction (μ) × normal force (N)

The normal force can be calculated using the formula:

Normal force (N) = mass (m) × acceleration due to gravity (g)

Given that the mass of the box is 100 kg and the acceleration due to gravity is approximately 9.8 m/s², we can calculate the normal force:

N = 100 kg × 9.8 m/s²

Now, let's calculate the frictional force:

Ff = 0.2 × N

Finally, we can calculate the acceleration of the box using Newton's second law of motion:

Force (F) = mass (m) × acceleration (a)

In this case, the force acting on the box is the pulling force of 300 N minus the frictional force. So we have:

F = 300 N - Ff

Now we can solve for acceleration:

a = (300 N - Ff) / m

Let's calculate the values step by step.

1. Calculate the normal force: - N = 100 kg × 9.8 m/s² = 980 N.

2. Calculate the frictional force: - Ff = 0.2 × N = 0.2 × 980 N = 196 N.

3. Calculate the acceleration: - a = (300 N - Ff) / m = (300 N - 196 N) / 100 kg = 104 N / 100 kg = 1.04 m/s².

Therefore, the box is moving with an acceleration of 1.04 m/s² and the frictional force acting on the box is 196 N.

Please note that the calculations assume that the box is moving horizontally on a flat surface and that there are no other significant forces acting on it.