A person weighing 60 kg runs at a speed of 8 km / h, catching up with a cart moving at a speed of 2.9
| July 7, 2021 | education
A person weighing 60 kg runs at a speed of 8 km / h, catching up with a cart moving at a speed of 2.9 km / h, he jumps on it. What will its speed be after that if its mass is 80 kg.
Task data: m1 (human weight) = 60 kg; m2 (trolley weight) = 80 kg; V1 (human running speed) = 8 km / h; V2 (initial trolley speed) = 2.9 km / h.
The speed of the joint movement of a person and a cart can be calculated using the law of conservation of momentum: (m1 + m2) * V = m1 * V1 + m2 * V2.
V = (m1 * V1 + m2 * V2) / (m1 + m2).
Let’s make the calculations: V = (60 * 8 + 80 * 2.9) / (60 + 80) = 712/140 ≈ 5.09 km / h.
Answer: A person with a cart will move at a speed of 5.09 km / h.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.
