This makes frequency lower as well as the pitch we hear.
ENERGY = POWER X TIME
=60 X 120=7200KWh
For an object`s motion, the Kinematic equation is,

Here, v is the final velocity and h is stands for the height of the object and a is the acceleration of the object.
As according to question,
and 
Thus, putting these values in above equation, we get

or


Therefore, initial velocity is 2.8 m/s
False because when the training higher there is less oxygen
Answer:
Maximum height attained by the model rocket is 2172.87 m
Explanation:
Given,
- Initial speed of the model rocket = u = 0
- acceleration of the model rocket =

- time during the acceleration = t = 2.30 s
We have to consider the whole motion into two parts
In first part the rocket is moving with an acceleration of a = 85.0
for the time t = 2.30 s before the fuel abruptly runs out.
Let
be the height attained by the rocket during this time intervel,

And Final velocity at that point be v

Now, in second part, after reaching the altitude of 224.825 m the fuel abruptly runs out. Therefore rocket is moving upward under the effect of gravitational acceleration,
Let '
' be the altitude attained by the rocket to reach at the maximum point after the rocket's fuel runs out,
At that insitant,
- initial velocity of the rocket = v = 195.5 m/s.
- a =

- Final velocity of the rocket at the maximum altitude =

From the kinematics,

Hence the maximum altitude attained by the rocket from the ground is
