A train accelerated from 10km/hr to 40km/hr in 2 min. How much distance does it cover in this period ? Assume that the tracks are straight . plzzz kindly answer
Answers
Correct question:-
A train accelerated from 10km/h to 40km/h in 2minutes.How much distance does the train cover in this period?Assume that the tracks are straight.
Given:-
•Initial velocity of the train(u)=10km/h
•Final velocity of the train(v)=40km/h
•Time taken=2mins
To find:-
•Distance covered by the train in given time.
Solution:-
At first,let us convert the speeds of the train into m/s and the time into seconds.
=>10km/h
=>10×5/18 (Since,1km/h=5/18 m/s)
=>50/18 m/s
=>40km/h
=>40×5/18
=>200/18 m/s
=>2mins=120 seconds. (Since,1min=60s)
From the 1st equation of motion:-
=>v=u+at
=>a=v-u/t
=>a=(200/18-50/18)/120
=>a=150/18/120
=>a=150/(18×120)
=>a=150/2160
=>a=5/72 m/s²
Hence,we have got the acceleration of the train as 5/72 m/s².
Now,from the 2nd equation of motion:-
=>s=ut+1/2at²
=>s=50/18×120+1/2×5/72×(120)²
=>s=6000/18+ (5/144)×14400
=>s=333.33+72000/144
=>s=333.33+500
=>s=833.33m or 0.83km
Thus,distance covered by the train is 833.33m or 0.83km.