The speed of the man and the chair after the book is thrown is 0.2 m/s.
The given parameters:
- mass of the book, m₁ = 2.1 kg
- speed of the book, u₁ = 7.2 m/s
- mass of the man, M = 70 kg
- mass of the book, m = 9.2 kg
The total mass of the man and the book is calculated as follows;
m₂ = 70 kg + 9.2 kg
m₂ = 79.2 kg
The speed of the man and the chair after the book is thrown is determined by applying the principle of conservation of linear momentum;
[tex]m_1 u_1 = m_2u_2\\\\u_2 = \frac{m_1u_1}{m_2} \\\\u_2 = \frac{2.1 \times 7.2}{79.2} \\\\u_2 = 0.2 \ m/s[/tex]
Thus, the speed of the man and the chair after the book is thrown is 0.2 m/s.
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