A rocket is fired vertically up from the ground with a resultant vertical acceleration of 10 m/s2. The fuel is finished in 1 min and it continues to move up. After how much time from then will the maximum height be reached?

v=10×60=600 m/s ---(i)As after burning of fuel the initial velocity from Eq. (i) is  600 m/s and gravity opposes the motion of rocket, so the time taken by it to reach the maximum height (for which v=0 ).0=600-gt t=60 si.e. after finishing fuel the rocket further goes up for 60 s, or 1 min.