Một đoàn tàu rời ga chuyển động nhanh dần, sau 20 s tàu đạt tốc độ 36 km/h. Tính gia tốc của tàu.
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Gia tốc của tàu được tính bằng công thức: $a = \frac{\Delta v}{\Delta t} = \frac{v_f - v_i}{t_f - t_i}$
Trong đó:
- $v_f$ là vận tốc cuối (10 m/s)
- $v_i$ là vận tốc đầu (0 m/s)
- $t_f$ là thời gian cuối (20 s)
- $t_i$ là thời gian đầu (0 s)
Vậy, $a = \frac{10 - 0}{20 - 0} = \frac{10}{20} = 0,5$ $m/s^2$.
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