The lifetime of a Π⁺ meson normally is 18 nanoseconds.In a large particle accelerator,scientists can create p+ mesons moving at speeds very close to the speed of light.What do the scientists observe when they measure the lifetime of a Π⁺ meson that is created at very high speed?
A)The Π⁺ meson lasts 18 nanoseconds.
B)The Π⁺ meson lasts much less than 18 nanoseconds.
C)The Π⁺ meson lasts much more than 18 nanoseconds.
D)The Π⁺ meson no longer decays,and remains as a stable particle.

Question

Quizplus · Accepted Answer

Due to the effects of time dilation as described by Einstein's theory of relativity, when a particle like the Π⁺ meson moves at speeds close to the speed of light, its observed lifetime from the laboratory frame of reference increases compared to its rest frame lifetime. This means scientists observe the meson lasting much longer than its normal 18 nanoseconds.

The Lifetime of a Π⁺ Meson Normally Is 18 Nanoseconds