Suggest two purposes of the copper braid.
Suggest one use of a coaxial cable for the transmission of electrical signals.
The noise power in a transmission cable remains constant at $7.6\,\mu\text{W}$. The smallest acceptable signal-to-noise ratio is $32\,\text{dB}$. Calculate the minimum acceptable signal power $P_{\text{MIN}}$ in the cable.
The signal enters the transmission cable with power $2.6\,\text{W}$. The cable has an attenuation per unit length of $6.3\,\text{dB km}^{-1}$. Use your answer in (i) to find the maximum continuous length $L$ of cable over which the signal can be sent.
The signal has input power $2.6\,\text{W}$ as it enters the transmission cable. The attenuation per unit length of the cable is $6.3\,\text{dB km}^{-1}$. Use your answer in (i) to find the greatest uninterrupted cable length $L$ over which transmission is possible.