Answer:
Explanation:
Given
initially mass is stretched to 
Let k be the spring Constant of spring
Therefore Total Mechanical Energy is 
Position at which kinetic Energy is equal to Elastic Potential Energy


it is given

thus 



Answer:
a). 6 seconds
b). 12 seconds
c). 176.4 meters
Explanation:
a). Equation to be applied to calculate the time taken by the rocket to reach at the peak height,
v = u - gt
where v = final velocity
u = initial velocity = 58.8 m per sec
g = gravitational pull = 9.8 m per sec²
t = duration of the flight
At the peak height,
v = 0
Therefore, 0 = 58.8 - (9.8)(t)
t = 
= 6 seconds
b). Total time of flight = 2(Time taken to go up)
= 2×6
= 12 sec
c). Formula to get the peak height is,

h = (58.8)6 - 
= 352.8 - 176.4
= 176.4 meters
distance d = 5 km = 5 x 1000 m = 5000 m
time taken = 25 minute = 25 x 60 sec = 1500 sec
average velocity V = d/t
V = 5000/1500
V = 3.33 m/s towards east