Answer:
2.00 seconds.
Explanation:
The following data were obtained from the question:
Initial velocity (u) = 9.81 m/s
Total time in air (T) =..?
Next, we shall determine the time taken for the rocket to reach it's maximum height. This can be obtained as follow:
Note: At maximum height, the final velocity is zero.
Initial velocity (u) = 9.81 m/s
Final velocity (v) = 0 m/s
Acceleration due to gravity (g) = 9.8 m/s²
Time to reach the maximum height (t) =.?
v = u – gt (since the rocket is going against gravity)
0 = 9.81 – 9.8t
Rearrange
9.8t = 9.81
Divide both side by 9.8
t = 9.81/9.8
t = 1.00 s
Therefore the time taken to reach the maximum height is 1.00 second.
Finally, we shall determine the total time spent by the rocket in the air as follow:
Time to reach the maximum height (t) = 1.00 s
Total time in air (T) =..?
T = 2t
T = 2 × 1.00
T = 2.00 s
Therefore, the total time spent by the rocket in the air is 2.00 seconds.
