Question

На вогонетку, маса якої дорівнює 800 кг, і яка рухається горизонтально, насипали 200 кг щебеню, внаслідок чого швидкість вагонетки зменшилась на 0,04 м/с. Визначте початкову швидкість руху вагонетки

Answer 1

P1=m1V1=800*0,2=160
p2=m2V2=1000*V2
p1=p2
160=1000*V2
V2=160/1000=0,16 м/с

Буду вдячний за "Кращу відповідь"

Answer 2

Calculation of Initial Velocity of the Cart

To determine the initial velocity of the cart, we can use the principle of conservation of momentum. According to this principle, the total momentum before and after an event remains constant, provided no external forces act on the system.

In this case, the initial momentum of the cart and the gravel is equal to the final momentum of the cart and the gravel. The momentum of an object is given by the product of its mass and velocity.

Let's denote the initial velocity of the cart as v, the mass of the cart as m1 (800 kg), the mass of the gravel as m2 (200 kg), and the final velocity of the cart as v' (0.04 m/s).

The initial momentum of the system is given by the sum of the momentum of the cart and the momentum of the gravel:

Initial momentum = m1 * v + m2 * 0

Since the gravel was initially at rest, its momentum is zero.

The final momentum of the system is given by the sum of the momentum of the cart and the momentum of the gravel after the gravel is added:

Final momentum = (m1 + m2) * v'

According to the principle of conservation of momentum, the initial momentum is equal to the final momentum:

m1 * v = (m1 + m2) * v'

Now we can solve this equation to find the initial velocity of the cart.

Let's substitute the given values into the equation:

800 kg * v = (800 kg + 200 kg) * 0.04 m/s

Simplifying the equation:

800v = 1000 * 0.04

800v = 40

v = 40 / 800

v = 0.05 m/s

Therefore, the initial velocity of the cart is 0.05 m/s.