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What belongs in each mystery box?

Every mystery box holds the same value. Make the two sides balance.

5 × ? + 666Equal values make a level balance.

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ScienceAges 16-18Physics (O Level): Motion, forces & energy
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Conservation of momentum in collisions

A 8 kg cart moving at 84 m/s collides with and couples to a stationary 6 kg cart on a frictionless track. Find their shared velocity immediately after the collision.

Apply conservation of linear momentum m₁u₁ = (m₁ + m₂)v to find the shared velocity after an inelastic collision.

8 kg (84 m/s) → [6 kg] → Coupled: (14 kg) v = ? · m₁u₁ = (m₁ + m₂)v
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