Question

Помогите пожалуйста решить задачу по физике. Тема: Законы сохранения 1. Человек массой 80 кг бегущий со скоростью 0,9м/с догоняет тележку, движущуюся со скоростью 0,4м/с и вскакивает на неё. Определите скорость тележки и человека, если масса тележки 50 кг​

Answer 1

Відповідь:

m1=80кг

m2=50кг

v1=0,9м/с

v2=0,4м/с

v3-?

m1*v1+m2*v2=(m1+m2)*v3

v3=(m1*v1+m2*v2)/(m1+m2)

v3=(80*0,9+50*0,4)(80+50)=0,7м/с

Пояснення:

Answer 2

Problem Analysis

To solve this problem, we can apply the law of conservation of momentum. According to this law, the total momentum before the interaction is equal to the total momentum after the interaction. In this case, the momentum of the person before jumping onto the cart is equal to the momentum of the person and the cart after the interaction.

Solution

Let's denote the mass of the person as m1 (80 kg), the mass of the cart as m2 (50 kg), the initial velocity of the person as v1 (0.9 m/s), and the initial velocity of the cart as v2 (0.4 m/s).

According to the law of conservation of momentum, we can write the equation:

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

where vf is the final velocity of the person and the cart after the interaction.

To find the final velocity, we can rearrange the equation as follows:

vf = (m1 * v1 + m2 * v2) / (m1 + m2)

Now, let's substitute the given values into the equation:

vf = (80 kg * 0.9 m/s + 50 kg * 0.4 m/s) / (80 kg + 50 kg)

Calculating this expression will give us the final velocity of the person and the cart after the interaction.

Calculation

Let's calculate the final velocity using the given values:

vf = (80 kg * 0.9 m/s + 50 kg * 0.4 m/s) / (80 kg + 50 kg)

vf = (72 kg·m/s + 20 kg·m/s) / 130 kg

vf = 92 kg·m/s / 130 kg

vf ≈ 0.708 m/s

Therefore, the final velocity of the person and the cart after the interaction is approximately 0.708 m/s.

Answer

The final velocity of the person and the cart after the interaction is approximately 0.708 m/s.