A question about sampling rate of cosine signal

1. How does sampling rate affect the signals?
2. How does the sampling rate affect the transmit digital signal?
3. What increases with sampling rate?

How does sampling rate affect the signals?

Sampling rate determines the sound frequency range (corresponding to pitch) which can be represented in the digital waveform. The range of frequencies represented in a waveform is often called its bandwidth.

How does the sampling rate affect the transmit digital signal?

It is the critical rate of sampling. If the signal xt is sampled above the Nyquist rate, the original signal can be recovered, and if it is sampled below the Nyquist rate, the signal cannot be recovered.

What increases with sampling rate?

There are several situations where an increased sampling rate does indeed increase the noise level, due to increased bandwidth of the sampling system or increase of sampling noise from the sampling system for example.