Why does a struck tuning fork sound louder when its handle is held against the table?

When a tuning fork is struck, it vibrates and produces sound. The sound is produced by the back-and-forth movement of the tines of the tuning fork, which causes the air around them to vibrate. The vibrations of the air are what we hear as sound.

When the handle of the tuning fork is held against the table, the vibrations of the tines are transmitted to the table. The table then acts as a sounding board, amplifying the vibrations and making the sound louder.

In addition, the table provides a larger surface area for the vibrations to spread out, which also helps to make the sound louder.

Finally, the table reflects the sound waves back towards the listener, which also contributes to the increase in loudness.