When a tuning fork vibrates over an open pipe and the air in the pipe starts to vibrate, the vibrations in the tube are caused by
a. harmonics.
b. beats.
c. reinforcement.
d. resonance.

The correct answer would be d. resonance

Resonance is the phenomenon which occurs when the frequency of the forced vibrations is almost equal to the natural frequency of the system. It amplifies the sound produced by the system.

Similarly, when the tuning fork is vibrated at the natural frequency of the open pipe, the air in the pipe starts vibrating at the same frequency and results in the increased amplitude of the sound.

they each offer a fresh glut of resources to the organisms that can arrive and exploit them. as individuals and new species continue to appear, they actively and passively alter the environment. competition for shared resources increases, local abiotic and biotic conditions shift, and the relative abundances of species change accordingly. the process is called ecological succession, and it is one of the earliest and most well-known concepts in ecology.

the scientific method.