A moving train is brought to rest within 10 seconds by applying brakes. What is the initial velocity, if the retardation due to brakes is 2.5 ms-2?
Step 1:Given data:
Step 2: Finding the initial velocity (u):
Now we know that;
Where,
We have,
Final velocity (v) = 0, a = -2.5 m/s2 (because of retardation), t = 10 s.
Therefore,
Hence, the initial velocity is equal to 25 m/s.