What is the maximum kinetic energy for harmonic motion with a reduced amplitude?

[Frouel]

Homework Statement

Before the rocket launch, the pendulum suspended in the cockpit made vibrations with the oscillation period of 2 s. During the vertical launch of the rocket, it was noticed that the pendulum made 5 oscillations in 6 s. Calculate the acceleration of the rocket. g = 10m / s2

The maximum kinetic energy of a harmonically vibrating body is 10mJ. Calculate its kinetic energy when the pendulum deflection is A / 3, where A - vibration amplitude

A stone was released into the shaft, which hit the bottom with a velocity of v = 40 m / s2. Assuming that the stone falls with the acceleration due to gravity g = 10 m / s2 and the voice velocity in the air is 340 m / s, calculate the time after which we will hear the stone knock against the bottom of the shaft.

Relevant Equations

Associate with simple harmonic motion and waves.

Solutions in a file.

 

[mjc123]

You haven't answered question 1. I'm not sure what you've done for question 2, but the answer seems wrong. Your working for question 3 is not visible.
Make some effort and type out your working.

 

[haruspex]

Further to the response above, please use a separate thread for each unrelated problem.
In question 2, you have calculated what the maximum KE would be if the amplitude were only one third. That is not what you are asked.