187. In a uniform magnetic field, a particle with charge $\alpha$ moves perpendicular to the magnetic field with velocity $v = 5 \times \frac{\text{m}}{\text{s}}$, and the acceleration resulting from the magnetic force is $4 \times 10^5 \, \frac{\text{m}}{\text{s}^2}$. How many gauss is the magnitude of the magnetic field? $$\left(\text{mass of particle } \alpha = 6.68 \times 10^{-27} \, \text{kg} \text{ and } e = 1.6 \times 10^{-19} \, \text{C}\right)$$ (1) $1.67$ (2) $2.78$ (3) $3.34$ (4) $4.05$
\textbf{187.} In a uniform magnetic field, a particle with charge $\alpha$ moves perpendicular to the magnetic field with velocity $v = 5 \times \frac{\text{m}}{\text{s}}$, and the acceleration resulting from the magnetic force is $4 \times 10^5 \, \frac{\text{m}}{\text{s}^2}$. How many gauss is the magnitude of the magnetic field?
$$\left(\text{mass of particle } \alpha = 6.68 \times 10^{-27} \, \text{kg} \text{ and } e = 1.6 \times 10^{-19} \, \text{C}\right)$$
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(1) $1.67$ \hspace{1cm} (2) $2.78$ \hspace{1cm} (3) $3.34$ \hspace{1cm} (4) $4.05$
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