Question

Consider an inertial frame S' moving at a speed $\frac{c}{3}$ away from another inertial frame S along the common x-axis, where c is the speed of light. As observed from S', a particle is moving with speed $\frac{c}{3}$ in the y' direction as shown in the figure. The speed of the particle as seen from S will be

• A. $\frac{\sqrt{15}}{9}c$
• B. $\frac{\sqrt{17}}{9}c$
• C. $\frac{\sqrt{21}}{9}c$
• D. $\frac{\sqrt{18}}{9}c$

Answer 1

Answer: (B)

$\frac{\sqrt{17}}{9}c$

Answer 2

The correct option is (B)