Question

Рыбак массой m запрыгивает в неподвижную стоящую на воде у берега лодку массой M.При этом лодка приходит в движение со скоростью v.Горизонтальная составляющая скорости рыбака в момент прыжка равна ϑ. Определите значение M, если m = 80 кг, v лодки = 3.4 м/с, v скорости рыбака = 6 м/c

Answer 1

Ответ:

61,2кг

Объяснение:

mϑ=(m+M)v

mϑ=mv+Mv

mϑ-mv=Mv

m(ϑ-v)/v=M

M=80кг(6м/с-3,4м/с)/3,4м/с=61,2кг

Answer 2

I can answer your question in detail. The fisherman of mass m jumps into a stationary boat of mass M standing on the water near the shore. As a result, the boat comes into motion with a speed v. The horizontal component of the fisherman's speed at the moment of the jump is equal to ϑ. Determine the value of M, if m = 80 kg, v of the boat = 3.4 m/s, v of the fisherman's speed = 6 m/s.

To solve this problem, we can use the law of conservation of momentum, which states that the total momentum of a system of bodies remains constant if no external forces act on the system. In this case, the system consists of the fisherman and the boat, and the external forces are negligible.

Before the jump, the fisherman has a momentum of mϑ in the horizontal direction, and the boat has zero momentum. After the jump, the fisherman and the boat move together with a common speed v, so their total momentum is (m + M)v. By equating the initial and final momenta, we get:

mϑ = (m + M)v

Solving for M, we get:

M = m(ϑ - v) / v

Substituting the given values, we get:

M = 80(6 - 3.4) / 3.4

M = 80(2.6) / 3.4

M = 208 / 3.4

M = 61.18 kg

Therefore, the mass of the boat is approximately 61.18 kg. This is the answer.