Question

Вагонетка массой m = 100 кг катится по горизонтальному участку дороги со скоростью v = 0,3 м/с. Как и на сколько изменится скорость вагонетки, если на неё насыпали M = 250 кг щебня?

Answer 1

Ответ: 0,09м/с

Объяснение:

Дано:

m1=100кг

V1=0,3м/с

m2=250кг

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V-?

По закону сохранения импульса:

m1*V1+m2*V2=V*(m1+m2)

m2*V2=0

V=m1*V1/(m1+m2)=100*0,3/(100+250)=0,09м/с

Answer 2

Calculation of the Change in Velocity of the Cart

To calculate the change in velocity of the cart when gravel is added to it, we can use the principle of conservation of momentum. The initial momentum of the cart is equal to the final momentum of the cart and gravel system.

The initial momentum of the cart is given by the product of its mass (m) and velocity (v): Initial momentum = m * v

After the gravel is added, the total mass of the system becomes the sum of the mass of the cart (m) and the mass of the gravel (M): Total mass = m + M

Let's denote the change in velocity of the cart as Δv. The final velocity of the cart after the gravel is added is given by: Final velocity = v + Δv

According to the principle of conservation of momentum, the initial momentum of the cart is equal to the final momentum of the system: Initial momentum = Final momentum

Therefore, we can write the equation as: m * v = (m + M) * (v + Δv)

To find Δv, we can rearrange the equation and solve for Δv: Δv = (m * v - m * v) / (m + M)

Now we can substitute the given values into the equation to calculate the change in velocity.

Given: - Mass of the cart (m) = 100 kg - Velocity of the cart (v) = 0.3 m/s - Mass of the gravel (M) = 250 kg

Substituting these values into the equation, we get: Δv = (100 kg * 0.3 m/s - 100 kg * 0.3 m/s) / (100 kg + 250 kg)

Simplifying the equation, we have: Δv = 0 m/s

Therefore, the change in velocity of the cart when 250 kg of gravel is added to it is 0 m/s. The velocity of the cart remains the same.