Answer:
L₀ = 0.0022 m = 2.2 mm
Step-by-step explanation:
Here, we will use the length contraction formula from the theory of relativity presented by Einstein:
where,
L = Relative length = 1.57 mm = 0.00157 m
L₀ = actual length at rest = ?
c = speed of light
v = relative speed = 70% of c = 0.7 c
Therefore,
L₀ = 0.0022 m = 2.2 mm