Question

The ratio of $\left(\frac{\text{charge}}{\text{mass}}\right)$ of a proton to that of an $\alpha$ particle is

• A. $1:2$
• B. $2:1$
• C. $4:1$
• D. $1:4$

Answer 1

Answer: (B)

$2:1$

Answer 2

$\frac{\left(q/ m\right)_{proton}}{\left(q /m\right)_{\alpha}}=\frac{q_{proton}}{q_{\alpha}}\times\frac{m_{\alpha}}{m_{proton}}$ $=\frac{1}{2}\times\frac{4}{1}$ $=2 : 1$