On a low-friction track, a 0.81 kg cart initially going at 1.85 m/s to the right collides with a cart of unknown inertia initially going at 2.17 m/s to the left. after the collision, the 0.81 kg cart is going at 1.32 m/s to the left, and the cart of unknown inertia is going at 3.22 m/s to the right. the collision lasts for 0.010 s.

The mass of unknown inertia is 0.476 kg.    

Explanation:

It is given that,

Mass of the cart, m₁ = 0.81 kg

Initial speed of cart, u₁ = 1.85 m/s (in right)

Initial speed of the other object, u₂ = -2.17 m/s (in left)

After the collision,

Final speed of the cart, v₁ = -1.32 m/s (in left)

Final speed of the other object, v₂ = 3.22 m/s (in right)

Let m₂ is the mass of the unknown inertia. Using the conservation of linear momentum to find the mass of unknown inertia.  

So, the mass of the unknown inertia is 0.476 kg. Hence, this is the required solution.

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