Answer:
The correct option is C: 0.31 s.
Explanation:
When the mass is then suddenly released we have:
Where:
F is the force
k: is the spring constant
Δy: is the spring displacement
Since the tension in the spring is zero, the force is the weight:

Where:
m is the mass of the object
g is the gravity
(1)
The oscillation period of the spring is given by:
(2)
By solving equation (1) for "k" and entering into equation (2) we have:

Since the spring will osclliates in a position between the initial position (when it is at rest) and the final position (when the mass is released and reaches the bottom), we have Δy = 2.5 cm = 0.025 m:
Hence, the oscillation period is 0.31 s.
The correct option is C: 0.31s.
I hope it helps you!
Answer:
It is one of the strongest materials in the world and can hold anything
Answer:
c. More intense IR absorption occur for those bonds having greater dipole moment changes with bond lengthening in a vibration.
Explanation:
When the molecules is exposed to the infrared radiation, the sample molecules absorb the radiation of wavelengths (specific to molecule) which causes change in the dipole moment of the sample molecules. The vibrational energy levels of the sample molecules consequently transfer from the ground state to the excited state.
Frequency of absorption peak is determined by vibrational energy gap.
Intensity of absorption peaks is related to change of dipole moment and possibility of transition of the energy levels.
Thus, by analyzing infrared spectrum,abundant structure information of the molecule can be known.
Hence, the correct answer to the question is
c. More intense IR absorption occur for those bonds having greater dipole moment changes with bond lengthening in a vibration.