Question

Мальчик прыгнул с лодки со скоростью 4 м/с, при этом лодка приобрела скорость 1 м/с. Какова масса лодки, если масса мальчика 50 кг?

Answer 1

10кг,тут всё элементарно

Answer 2

Calculation of the Mass of the Boat

To calculate the mass of the boat, we can use the principle of conservation of momentum. According to this principle, the total momentum before the boy jumps off the boat is equal to the total momentum after the boy jumps off.

The momentum of an object is calculated by multiplying its mass by its velocity. Let's denote the mass of the boat as M and the velocity of the boat before the boy jumps off as V1. The mass of the boy is given as 50 kg, and his velocity before jumping off is 4 m/s. The velocity of the boat after the boy jumps off is given as 1 m/s.

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

(M * V1) = (M * V2) + (m * v)

Where: - V1 is the velocity of the boat before the boy jumps off (4 m/s) - V2 is the velocity of the boat after the boy jumps off (1 m/s) - M is the mass of the boat (unknown) - m is the mass of the boy (50 kg) - v is the velocity of the boy before jumping off (4 m/s)

Substituting the given values into the equation, we get:

(M * 4) = (M * 1) + (50 * 4)

Simplifying the equation:

4M = M + 200

3M = 200

M = 200 / 3

Therefore, the mass of the boat is approximately 66.67 kg.

Please note that the above calculation assumes an idealized scenario where there are no external forces acting on the boat and the boy. In reality, there might be other factors to consider, such as friction and air resistance, which could affect the accuracy of the result.