why does a telephone makes sound travel faster than sound
It's actually not true that a telephone makes sound travel faster than sound. Sound travels at a certain speed through a medium, such as air, and this speed is constant. The speed of sound in air at room temperature is approximately 343 meters per second (about 1,125 feet per second).

When you speak into a telephone, your voice is converted into an electrical signal, which is then transmitted through wires or wireless communication channels to another telephone. This signal travels at the speed of light, which is much faster than the speed of sound. However, the signal itself is not sound; it is an electrical signal that can be converted back into sound at the other end of the line.

So while a telephone can transmit sound over long distances much more quickly than sound can travel through the air, it's not accurate to say that the telephone makes sound itself travel faster than its normal speed.
Thank you for your explanation! Is there a way to transmit a signal faster than light?
You are welcome. According to the current scientific understanding, there is no way to transmit a signal faster than light in a vacuum. Light travels at the maximum speed possible in the universe, which is about 186,282 miles per second (299,792 kilometers per second). Anything that travels faster than light would violate the principle of causality, which states that the cause must precede the effect in time.

However, there are some hypothetical scenarios that might allow for apparent faster-than-light communication, such as using wormholes or quantum entanglement. These are not proven or widely accepted by the scientific community, and they may have their own limitations and paradoxes. Therefore, they are not considered as realistic or practical ways of transmitting a signal faster than light.