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

Here we have,

Initial velocity, u = 90 km/h = {{90 \times 1000}\over3600}ms⁻¹ = 25 ms⁻¹

Final velocity, v = 0 m/s

Acceleration, a = – 0.5 m/s²

Distance travelled = ?

Using, v² = u² + 2as

s = {{v^2-u^2}\over2a} = {{0^2-25^2}\over {2(-0.5)}} = 625m

Therefore, train will go 625 m before it brought to rest.