Answer: The velocity of released alpha particle is [tex]1.127\times 10^7m/s[/tex]
Explanation:
According to law of conservation of momentum, momentum can neither be created nor be destroyed until and unless, an external force is applied.
For a system:
[tex]m_1v_1=m_2v_2[/tex]
where,
[tex]m_1\text{ and }v_1[/tex] = Initial mass and velocity
[tex]m_2\text{ and }v_2[/tex] = Final mass and velocity
We are given:
[tex]m_1=238u\\v_1=1.895\times 10^{5}m/s\\m_2=4u\text{ (Mass of }\alpha \text{ -particle)}\\v_2=?m/s[/tex]
Putting values in above equation, we get:
[tex]238\times 1.895\times 10^5=4\times v_2\\\\v_2=\frac{238\times 1.895\times 10^5}{4}=1.127\times 10^7m/s[/tex]
Hence, the velocity of released alpha particle is [tex]1.127\times 10^7m/s[/tex]