Question

Человек массой 60 кг, бежавший со скоростью 4м/с, прыгнул в тележку. Какова масса тележки, если она начала двигаться со скоростью 1м/с?

Answer 1

MV = V'(m + M);
m + M = mV/V' = 60*4/1 = 240;
M = 240 - 60 = 180кг.

Answer 2

Calculation of the Mass of the Cart

To determine the mass of the cart, we can use the principle of conservation of momentum. According to this principle, the total momentum before the person jumps into the cart is equal to the total momentum after the person jumps.

Let's denote the mass of the person as m1 (60 kg) and the mass of the cart as m2 (unknown). The initial velocity of the person is v1 (4 m/s), and the final velocity of the person and the cart together is v (1 m/s).

Using the conservation of momentum equation, we have:

m1 * v1 = (m1 + m2) * v Substituting the given values:

60 kg * 4 m/s = (60 kg + m2) * 1 m/s

Simplifying the equation:

240 kg·m/s = 60 kg + m2

To solve for m2, we subtract 60 kg from both sides of the equation:

m2 = 240 kg·m/s - 60 kg

Therefore, the mass of the cart is 240 kg - 60 kg = 180 kg.

So, the mass of the cart is 180 kg.