A train travels at 1.3 m/s^2. How long to reach a speed of 75km/h

train-travels

#1

A train travels at 1.3 m/s^2. How long to reach a speed of 75km/h

Answer:

Since the train started from rest initial velocity (u) =0 m/s
Acceleration (a) = 1.3 m/s^2
Final velocity (V) = 75km/h
(converting km/h to meter/sec or m/s)
=75*1000meter/3600sec (1km=1000mtrs,1hr=3600secs)
(v) =20.83m/s
Time(t) = ?
From the eq of kinematics,
V=u+at…(1)
substituting all the values of u,v,a,t in eq…(1)
20.83m/s = 0m/s + (1.3m/s^2)(t)
20.83m/s= (1.3m/s^2)(t)
(t)=(20.83)/(1.3)=16.025secs
–>It takes 16.025secs to reach the speed of 75km/h