For a range of 5 nautical miles, the RADAR...

Question 1 of 2707042oOxH1Zt6ez5fw1OKQy

For a range of 5 nautical miles, the RADAR pulse repetition frequency should be:

Question 1 of 27070

For a range of 5 nautical miles, the RADAR pulse repetition frequency should be:

🔍 Key Concepts

• Pulse Repetition Frequency (PRF) and how it relates to maximum unambiguous range on marine radar • The relationship: higher PRF = shorter maximum unambiguous range, lower PRF = longer maximum unambiguous range • Typical order of magnitude (Hz / kHz / MHz) used for PRF on short‑range marine radar (a few miles)

💭 Think About

• Think about how long it takes a radar pulse to travel out 5 nautical miles and back, and how that time limits how often you can transmit pulses without causing range ambiguity. • Compare the travel time for 5 nautical miles with the period of each option (the inverse of the frequency). Which options would send out the next pulse too quickly, before echoes from the previous one can return? • Look at the units (Hz, kHz, MHz). Which are realistic for a marine radar’s PRF for a few‑mile range, and which are clearly too high or too low?

✅ Before You Answer

• Convert 5 nautical miles to meters and then to two‑way travel time using speed of radio waves (~3×10^8 m/s). • For each option, compute the pulse period: $T = 1/f$ . Compare this to the required two‑way travel time for 5 NM. • Eliminate any option where the pulse period is shorter than the time needed for the echo from 5 NM to return, as this would cause range ambiguity.