Question

Мальчик массой 22кг , бегущий со скоростью 2,5 м/с , вскакивает сзади на платформу массой 12 кг.Чему равна скорость платформы с мальчиком.

Answer 1

Используя закон сохранения импульса m1*V1=(m1+m2)*V
V=m1*V1/m1+m2=22*2,5/22+12=1,62 м/с

Answer 2

Calculation of the Platform's Velocity

To determine the velocity of the platform with the boy on it, we can use the principle of conservation of momentum. According to this principle, the total momentum before the boy jumps onto the platform should be equal to the total momentum after he lands on it.

The momentum of an object is calculated by multiplying its mass by its velocity. Let's denote the mass of the boy as m1 (22 kg) and his velocity as v1 (2.5 m/s). The mass of the platform is denoted as m2 (12 kg), and we need to find the velocity of the platform with the boy, denoted as v2.

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

m1 * v1 = (m1 + m2) * v2

Substituting the given values:

22 kg * 2.5 m/s = (22 kg + 12 kg) * v2

Simplifying the equation:

55 kg * m/s = 34 kg * v2

Now, we can solve for v2:

v2 = (55 kg * m/s) / 34 kg

Calculating the value:

v2 ≈ 1.618 m/s

Therefore, the velocity of the platform with the boy is approximately 1.618 m/s.