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Find the time taken if the speed of a train increased rom 72km/h to 90km/h for 234km

User Ducminh
by
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1 Answer

3 votes

Answer:

2.89 hours

Step-by-step explanation:

given :

Vo = 72 km/h

Vt = 90 km/h

S = 234 km

find : the time taken (t) = ?

solution :

2.a.s = Vt² - Vo²

2.a.(234) = 90²- 72²

468.a = 8100 - 5184

= 2916

a = 2916/468 = 6.23 km/h²

so,

t = (Vt-Vo) /a

= (90-72)/ 6.23

= 18/ 6.23

= 2.89 hours

User Antelove
by
5.1k points