Two blocks of masses 10 kg and 30 kg are placed along a vertical line. The first block is raised through a height of 7 cm. By what distance should the second mass be moved to raise the centre of mass by 1 cm?

Explanation

To solve the problem, we need to find out how far the second block (30 kg) should be moved to raise the center of mass of the system by 1 cm after the first block (10 kg) is raised by 7 cm.

### Step-by-Step Solution:

1. **Identify the Masses and Initial Heights**:
- Let \( m_1 = 10 \, \text{kg} \) (mass of the first block).
- Let \( m_2 = 30 \, \text{kg} \) (mass of the second block).
- Let \( h_1 = 0 \, \text{cm} \) (initial height of the first block).
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