Question

A piece of thin card is held against a cog wheel .when wheel is turned voice is produced. how can the pitch be increased.

Answer 1

Answer:

By increasing the speed of a cog wheel the pitch of sound is also increased.

Explanation:

By increasing the speed of a cog wheel the pitch of sound is also increased.

As when cog wheel’s speed increases the frequency of sound is also increased, and we know that  

frequency ∝ pitch  

As both have direct relation so increasing the speed of the wheel can cause an increase in the pitch of sound.

Answer 2

Answer:

By increasing the speed of a cog wheel the pitch of sound is also increased. Explanation: By increasing the speed of a cog wheel the pitch of sound is also increased. As both have direct relation so increasing the speed of the wheel can cause an increase in the pitch of sound.