Question

A train is travelling at a speed,of 90 km h-1. Brakes are applied so as to produce a uniform acceleration of -0.5 m s-2. Find how far the train will go before it is brought to rest

Answer 1

625 m is the correct answer..

Answer 2

Answer:

625 metres.

Explanation:

Given :

A train is traveling at a speed of 90 km/h.

Brakes are applied so as to produce a uniform acceleration of -0.5 m/s².

Find how far the train will go before it is brought to rest.

Solution :

We know that,

Distance traveled (s)

⇒ v² - u² = 2as

Where,

Initial veocity (u) = 90 km/h = $\frac{5}{18}\times 90$ m/s =  25 m/s.

Final velocity (v) = 0 m/s

acceleration (a) = -0.5 m/s²

⇒ v² - u² = 2as

⇒ (0)² - (25)² = 2(-0.5)s

⇒ -625 = -s

⇒ s = 625m