If the elapsed time for a RADAR echo is 62 microseconds, what is the distance to the object in nautical miles?

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Multiple Choice

If the elapsed time for a RADAR echo is 62 microseconds, what is the distance to the object in nautical miles?

Radar distance comes from the round-trip travel time of the pulse. The distance to the object is half the round-trip time multiplied by the speed of light, then converted from meters to nautical miles (1 nm = 1852 m). A handy rule of thumb is that each nautical mile corresponds to about 12.36 microseconds of round-trip time. For 62 microseconds: - Convert to meters for the round trip: 299,792,458 m/s × 62 μs (62 × 10^-6 s) ≈ 18,585 m - One-way distance: ≈ 9,292.5 m - Convert to nautical miles: 9,292.5 m ÷ 1852 ≈ 5.0 nm So the object is about 5 nautical miles away.

Radar distance comes from the round-trip travel time of the pulse. The distance to the object is half the round-trip time multiplied by the speed of light, then converted from meters to nautical miles (1 nm = 1852 m). A handy rule of thumb is that each nautical mile corresponds to about 12.36 microseconds of round-trip time.

For 62 microseconds:

  • Convert to meters for the round trip: 299,792,458 m/s × 62 μs (62 × 10^-6 s) ≈ 18,585 m

  • One-way distance: ≈ 9,292.5 m

  • Convert to nautical miles: 9,292.5 m ÷ 1852 ≈ 5.0 nm

So the object is about 5 nautical miles away.

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