Answer:
A. 35 m/s
B. 61.25 m
C. 35 m/s
Step-by-step explanation:
From the question given above, the following data were obtained:
Time of flight (T) = 7 s
Next, we shall determine the time taken to reach the maximum height. This can be obtained as follow:
Time of flight (T) = 7 s
Time (t) take to reach maximum height =?
T = 2t
7 = 2t
Divide both side by 2
t = 7/2
t = 3.5 s
A. Determination of the Lauch velocity.
Time (t) to reach maximum height = 3.5 s
Final velocity (v) = 0 (at maximum height)
Acceleration due to gravity (g) = 10 m/s²
Initial velocity (u) =?
v = u – gt (since the rocket is going against gravity)
0 = u – (10 × 3.5)
0 = u – 35
Collect like terms
0 + 35 = u
u = 35 m/s
Thus, the Lauch velocity is 35 m/s
B. Determination of maximum height reached by the rocket.
Final velocity (v) = 0 (at maximum height)
Acceleration due to gravity (g) = 10 m/s²
Initial velocity (u) = 35 m/s
Maximum height (h) =?
v² = u² – 2gh (since the rocket is going against gravity)
0² = 35² – (2 × 10 × h)
0 = 1225 – 20h
Rearrange
20h = 1225
Divide both side by 20
h = 1225 / 20
h = 61.25 m
Thus, the maximum height reached by the rocket is 61.25 m
C. Determination of the velocity before hitting ground.
Initial velocity (u) = 0 m/s
Acceleration due to gravity (g) = 10 m/s²
Time (t) to reach the ground from the maximum height = 3.5 s
Final velocity (v) =?
v = u + gt (since the rocket is moving towards gravity)
v = 0 + (3.5 × 10)
v = 0 + 35
v = 35 m/s
Thus, the velocity of the rocket before hitting ground is 35 m/s