a.A sinewave has a period (duration of one cycle) of 35 μs. What is its corresponding frequency, in kHz, expressed to 3 significant figures? (see Study Note 7.1in the Using Numbers (maths) booklet).If the frequency of this sinewave is now reduced by a factor of 2.5, using the value calculated above to 3 significant figures, what will be the new period? Express your answer in μs, to 3 significant figures.(8 marks)
b.Convert the following dotted decimal IP address into binary (see Block 3, Part 2).60.231.159.202(6 marks)
c.In a high-quality coaxial cable, the power drops by a factor of 10 approximately every 5 km. If the original signal power is 0.25 W (=2.5 x 10-1), how far will a signal be transmitted before the power is attenuated to 25 μW? As part of your answer, include a Table showing the signal power vs. distance in 5 km intervals (like Table 1.2 in Section 1.4.4). If optical fibre is used instead of the coaxial cable, briefly explain how you would expect the above calculated distance value to change (see Section 1.4.4). You are not required to include another Table.(8 marks)
d.Express the following 48-bit binary MAC address in hexadecimal (see ‘Using Numbers (maths)’ booklet).11111100 – 01111110 – 10001011 – 11010110 – 00110101 – 10011010(8 marks)
Sample Solution