Question

A bus moving with the velocity of 72km/hr has acceleration 0.5m/s2. how long will take to gain the velocity of 27m/s

Answer 1

Answer:

14 second

Step-by-step explanation:

u=72 km/h

=72*(5/18) m/s

=20m/s

v=27 m/s

a=0.5m/s²

let, time be t

According to the 1st formula of motion

v=u+at

=>27=20+0.5*t

=>27=20+0.5t

=>20+0.5t=27

=>0.5t=27-20

=>0.5t=7

=>t=7/0.5

=>t=(7*10)/5

=>t=70/5

=>t=14

Therefore, Time=14 second

Answer 2

Answer:

14 sec

Step-by-step explanation:

u=72km/hr = 72×1000/60×60=7200/3600=20m/s

a=0.5m/s²

V=27m/s

now using the formula,

v =u+at

27=20+0.5×t

0.5t=27-20

0.5t=7

t=7/0.5

ans = 14sec