Question

"короткое плечо колодца с журавлем имеет длину 0.5м,а длинное плечо-4.5м .на сколько метров опустится конец длинного плеча,когда конец короткого поднимется на 0.4"

Answer 1

Представим треугольник, образованный изначальным положением плеча, конечным положением плеча и его подъёмом. Он будет подобен аналогичному треугольнику для другого плеча (потому что угол подъёма одного равен углу подъёма второго). Значит конец длинного плеча опустится на высоту, пропорциональную подъёму короткого плеча: х/0,4 = 4,5/0,5
х=0,4*(4,5/0,5)=0,4*9=3,6 м

Answer 2

Solution:

To solve this problem, we can use the principle of moments, which states that the clockwise moment about a pivot is equal to the anticlockwise moment about the same pivot.

Let's denote: - Length of the short arm of the lever as 0.5m - Length of the long arm of the lever as 4.5m - Upward movement of the short arm as 0.4m

We can use the formula for moments: Force × Distance. In this case, the force is the weight acting on the lever.

First, we need to find the force acting on the lever. The force can be calculated using the formula: Force = Weight × Gravity, where gravity is approximately 9.81 m/s^2.

Now, let's calculate the force acting on the lever and then use it to find the downward movement of the long arm.

Calculation:

The force acting on the lever can be calculated using the weight formula: Force = Weight × Gravity

Assuming the weight is 1 kg, the force can be calculated as: Force = 1 kg × 9.81 m/s^2 = 9.81 N

Now, we can use the principle of moments to find the downward movement of the long arm.

The principle of moments states that the clockwise moment about a pivot is equal to the anticlockwise moment about the same pivot.

Using the formula for moments: Force × Distance, we can calculate the downward movement of the long arm.

The equation for the principle of moments can be written as: Force × short arm distance = Weight × long arm distance

Substituting the values: 9.81 N × 0.5m = Weight × 4.5m

Solving for Weight: Weight = (9.81 N × 0.5m) / 4.5m = 1.09 N

Now, we can use this weight to find the downward movement of the long arm when the short arm is raised by 0.4m.

Using the formula for moments: Force × Distance = Weight × Distance

Substituting the values: 1.09 N × 4.5m = Weight × (4.5m - x)

Where x is the downward movement of the long arm.

Solving for x: x = 4.5m - (1.09 N × 4.5m) / 1.09 N

After calculating, we find: x ≈ 4.5m - 4.5m = 0m

Answer:

When the end of the short arm is raised by 0.4m, the end of the long arm will not move downward; it will remain at the same level.