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Class 9
Science
Motion
a train is travelling at a speed of 90 km h 1 bra...

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:

Initial speed of the train, u = 90 km/h = 90 x 1000 / 60 x 60 = 25 m/s

Final speed of the train, v = 0

Acceleration = −0.5 m s^-2

Using equation of motion:

v² = u² + 2 as

(0)² = (25)² + 2 (−0.5) s

0 = 625 - s

s = 625 m

Where, s is the distance covered by the train

The train will cover a distance of 625 m before it comes to rest.

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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.

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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.

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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.