Question

4.Камень массой в 1т упал с вершины Имантауской сопки . Скорость камня до столкновения с другим камнем, массой в 2т , была 72км/час. b) Какой кинетической энергией обладал камень во время столкновения? [1]с) С какой скоростью начнет двигаться камень после столкновения? [2]​

Answer 1

Ответ:

1)m=1T=1000кг

V=72км/час=20м/с

Ек=m*V^2/2=1000*20^2/2=1000*400/2=200000Дж

2)0 м/с, так как Кинетическая энергия не имеет скорости  

Answer 2

Calculation of Kinetic Energy:

To calculate the kinetic energy of an object, we can use the formula:

Kinetic Energy (KE) = 0.5 * mass * velocity^2

In this case, the mass of the stone is 1 ton (1000 kg) and the velocity before the collision is 72 km/h. We need to convert the velocity to meters per second (m/s) before plugging it into the formula.

Converting 72 km/h to m/s: 1 km/h = 1000 m/3600 s So, 72 km/h = (72 * 1000) / 3600 = 20 m/s

Now, we can calculate the kinetic energy of the stone before the collision:

KE = 0.5 * 1000 kg * (20 m/s)^2

Calculating this, we find that the stone had a kinetic energy of 20,000 Joules at the time of the collision. [[1]]

Calculation of Post-Collision Velocity:

To calculate the post-collision velocity of the stone, we can use the principle of conservation of momentum. According to this principle, the total momentum before the collision is equal to the total momentum after the collision.

The momentum of an object is given by the formula:

Momentum (p) = mass * velocity

Before the collision, the momentum of the stone is:

Momentum before collision = 1000 kg * 20 m/s

After the collision, the momentum of the stone will be the sum of the momenta of both stones. The mass of the second stone is 2 tons (2000 kg), and we need to find its velocity after the collision.

Let's assume the velocity of the second stone after the collision is v m/s. The momentum of the second stone after the collision is:

Momentum of second stone after collision = 2000 kg * v m/s

According to the principle of conservation of momentum, the total momentum before the collision is equal to the total momentum after the collision:

Momentum before collision = Momentum of first stone after collision + Momentum of second stone after collision

Substituting the values, we get:

1000 kg * 20 m/s = 1000 kg * v m/s + 2000 kg * v m/s

Simplifying the equation, we find:

20,000 kg m/s = 3000 kg * v m/s

Dividing both sides by 3000 kg, we get:

v = 20,000 kg m/s / 3000 kg

Calculating this, we find that the post-collision velocity of the stone is approximately 6.67 m/s. [[2]]