A particle moves in a straight line with a constant acceleration. It changes its velocity from 10 m/s to 20 m/s while passing through a distance of 135 m in time of “t” second.  Then value of  time “t” is

displacement =( average velocity )time S    =    (U+V2)​​  t substitute given values initial velocity u=10m/s; final velocity v=20m/s; displacement s=135m in above equation135    =    (10+202)​​  t⇒      t     =    9 sec