Question

Find the acceleration if a train driver applies breaks and train travelling with speed 100km/hour halts in 5 min

Answer 1

It is given that train travelling with speed of 100 km/h halts after 5 minutes after applying brakes.

We have to find acceleration of train .

Solution

Here, initial speed (u) = 100 km/h

➼ Initial speed (u) = 100 × (5/18) m/s

➼ Initial speed (u) = 27.78 m/s

As the train halts, so final velocity i.e. v = 0

Again, time = 5 minutes.

➼ Time (t) = (5 × 60) s

➼ Time (t) = 300 s

We know that,

☛ a = (v - u)/t

Where,

• a = acceleration
• v = final speed
• u = initial speed.
• t = time

Putting values we get :

⟿ a = (0 - 27.78)/300

⟿ a = -27.78/300

⟿ a = -0.09 m/s²

[Note : Negative sign shows retardation - working against the motion ]

Hence, acceleration of train = -0.09 m/s²