An Unstable Particle Is Moving at a Speed Of $1.6 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s }$

Short Answer

An unstable particle is moving at a speed of $1.6 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s }$ relative to a laboratory. Its lifetime is measured by a stationary observer in the laboratory to be $6.8 \times 10 ^ { - 6 } \mathrm {~s}$ . What is the lifetime of the particle as measured in the rest frame of the particle? $\left( c = 3.0 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } \right)$