Explanation:

- A boy with a mass of 52 kg jumps onto a stationary cart weighing 3 kg.

- The boy's horizontal velocity is 2 m/s.

- We need to find the speed of the cart after the boy jumps onto it.

- Use the conservation of momentum: initial momentum = final momentum.

- Initial momentum = mass of boy × velocity of boy = 52 kg × 2 m/s = 104 kg·m/s.

- Final momentum = (mass of boy + mass of cart) × velocity of boy and cart.

- Set them equal: 104 kg·m/s = (52 kg + 3 kg) × speed.

- Solve for speed: 104 kg·m/s = 55 kg × speed ? speed = 104/55 m/s = 1.89 m/s.

Correct Answer: Option 2, 1.89 m/s

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