Question

Рабочий с помощью лома поднимает камень массой m=120 кг, прикладывая к свободному концу лома F=100 Н. Какова длина лома, если расстояние от его конца до точки соприкосновения лома и камня l1=10 см? Коэффициент g принять равным 10 Н/кг. Массу лома и размера камня не учитывать.

Answer 1

Пусть L- длина лома Плече приложенное к камню L1=0,1, lheujt L-L1
 По правилу моментов сил  m*g*L1=F*(L-L1)
m*g*L1=F*L-F*L1
L=L1*(m*g-F)/F=0,1*(120*10-100)/100=1,1м

Answer 2

Calculating the Length of the Lever

To calculate the length of the lever, we can use the principle of moments, which states that the sum of the moments of the forces acting on an object is zero when the object is in equilibrium. The formula for the principle of moments is:

F1 × l1 = F2 × l2

Where: - F1 is the force applied at one end of the lever - l1 is the distance from the force to the fulcrum - F2 is the force applied at the other end of the lever - l2 is the distance from the force to the fulcrum

In this case, the force applied at one end of the lever is F = 100 N and the distance from the force to the fulcrum is l1 = 10 cm.

Calculating the Length of the Lever

Using the principle of moments, we can rearrange the formula to solve for l2:

l2 = (F1 × l1) / F2

Substitute the given values: l2 = (100 N × 10 cm) / F2

Now, we need to convert the force and distance to the appropriate units for calculation.

Unit Conversion

The force is given in Newtons (N) and the distance is given in centimeters (cm). We need to convert the distance to meters for consistent units.

1 cm = 0.01 m

So, l1 = 10 cm becomes l1 = 0.1 m.

Calculation

Now, we can calculate the length of the lever:

l2 = (100 N × 0.1 m) / F2

Final Calculation

Given that the force applied is F = 100 N, the length from the force to the fulcrum is l1 = 0.1 m, and the force applied at the other end of the lever is F2 = 120 kg × 10 N/kg = 1200 N (using the given coefficient g = 10 N/kg), we can calculate the length l2.

l2 = (100 N × 0.1 m) / 1200 N

l2 = 0.01 m

So, the length of the lever is 0.01 meters.