Concept explainers
(a)
The maximum altitude of the rocket.
Answer to Problem 82QAP
The maximum altitude of the rocket is
Explanation of Solution
Given:
a1 =
a2 =
t1 = 15 sec
t2 = 12 sec
Formula used:
S = distance travelled
u = initial velocity
a = acceleration
t = time taken
Calculation:
During first stage, the height reached is,
At the end of first stage speed is,
During second stage, the height reached is,
At the end of second stage speed is,
At the end of second stage, the rocket will be under the effect of gravity, so it will continue to move upwards up to a point where its kinetic energy will be zero.
The time duration for reaching the maximum altitude from the end of second stage is,
The distance between the end of second stage and maximum altitude is,
So, the maximum height is,
(b)
The average speed and average velocity when the rocket fall back to launch pad.
Answer to Problem 82QAP
The average speed is
Explanation of Solution
Given:
The maximum altitude is
Calculation:
Once rocket reaches the maximum height, it will start to fall and reach the launch pad on Earth surface.
The time duration taken by rocket to fall back is,
Total time duration of flight,
Total distance travelled is,
So average speed will be,
Since, the initial and final position of rocket is same, so the net displacement is zero. Therefore, the average velocity will be,
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Chapter 2 Solutions
COLLEGE PHYSICS-ACHIEVE AC (1-TERM)
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