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A 1200 kg car going East at 20 m/s hits another car (1000 kg) that is moving head-on at 25 m/s. The first car bounces back at m/s, how fast and in which direction does the second car go?

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Answer:

The velocity of the second car after the collision, v₂ = 11 m/s

The second car bounces back from its original direction.

Step-by-step explanation:

Given data,

The mass of the car going east, m₁ = 1200 kg

The velocity of the car going east, u₁ = 20 m/s

The mass of the second car, m₂ = 1000 kg

The velocity of the second car, u₂ = -25 m/s

The first car bounces back at v₁ = -10 m/s

According to the law of conservation of momentum

m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂

v₂ = (m₁u₁ + m₂u₂ - m₁v₁) / m₂

Substituting the given values,

v₂ = (1200 x 20 - 1000 x 25 + 1200 x 10)/1000

v₂ = 11 m/s

Hence, the velocity of the second car after the collision, v₂ = 11 m/s

The second car bounces back from its original direction.

User Kishore Yekkanti
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