Jawabanmu

2014-03-01T11:42:41+07:00
T1 = 28c
T2 = 78c
Δt = 78 - 28 = 28c
Lo = 80 m
α = 0.000017/c
Δl = ?
Δl =
Lo . α . Δt
80 m . 0.000017/c . 50 c
0.068 m
6.8 cm