The speed of the train after an additional 5 s has elapsed is 9.45 m/s
This is defined as the rate of change of velocity which time. It is expressed as
a = (v – u) / t
Where
a = (v – u) / t
a = (4.9 – 0) / 5.4
a = 4.9 / 5.4
a = 0.91 m/s²
a = (v – u) / t
0.91 = (v – 4.9) / 5
Cross multiply
v – 4.9 = 0.91 × 5
v – 4.9 = 4.55
Collect like terms
v = 4.55 + 4.9
v = 9.45 m/s
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