Question

Из неподвижной лодки масса которой 80 кг прыгает на берег мальчик . масса мальчика сорок килограмм скорость его при прыжке 2 m/c. какую скорость приобрила лодка?

Answer 1

Дано:                                                  Решение.
m₁ = 80 кг
m₂ = 40 кг              По закону сохранения импульса: m₁v₁ = m₂v₂
v₂ = 2 м/с              Тогда:
-----------------                          v₁ = m₂v₂/m₁ = 40*2/80 = 1 (м/с)
Найти:
v₁ = ?

Ответ: лодка приобрела скорость 1 м/с

Answer 2

Масса1 =80 кг
масса 2= 40кг
скорость 2 =2 м/с

Скорость1= 2*40:80= 1 метр в секунду. 

Ответ 1 м/с

Answer 3

Calculation of the Boat's Velocity

To calculate the velocity acquired by the boat when the boy jumps onto the shore, we can use the principle of conservation of momentum. According to this principle, the total momentum before the jump is equal to the total momentum after the jump.

The momentum of an object is given by the product of its mass and velocity. Let's denote the mass of the boat as m1 and the mass of the boy as m2. The velocity of the boat before the jump is v1, and the velocity of the boy before the jump is v2. After the jump, the boat and the boy move in opposite directions.

Using the conservation of momentum, we can write the equation:

(m1 * v1) + (m2 * v2) = (m1 * v1') + (m2 * v2')

where v1' is the velocity of the boat after the jump, and v2' is the velocity of the boy after the jump.

Given the following values: - Mass of the boat (m1) = 80 kg - Mass of the boy (m2) = 40 kg - Velocity of the boy before the jump (v2) = 2 m/s

We need to find the velocity of the boat after the jump (v1').

To solve for v1', we rearrange the equation:

v1' = [(m1 * v1) + (m2 * v2) - (m2 * v2')] / m1

Since the boy jumps onto the shore, his velocity after the jump (v2') is zero. Plugging in the values, we get:

v1' = [(80 kg * v1) + (40 kg * 2 m/s)] / 80 kg

Simplifying the equation:

v1' = (80 kg * v1 + 80 kg) / 80 kg

v1' = v1 + 1 m/s

Therefore, the velocity acquired by the boat after the boy jumps onto the shore is equal to the velocity of the boat before the jump plus 1 m/s.

Please note that the initial velocity of the boat (v1) is not provided in the question. If you have the value of v1, you can substitute it into the equation to calculate v1'.