🔍 Key Concepts

• Speed of radio waves/radar pulses (speed of light) in meters per second • Relationship among distance, speed, and time • Conversion between meters and nautical miles, and between seconds and microseconds (µs)

💭 Think About

• Start from the idea that radar pulses travel at (approximately) the speed of light. How far does the pulse go in a given time, and why do you need to account for the out-and-back path? • Write an equation using distance = speed × time, and then solve for the one-way distance to the target in nautical miles per microsecond. • Convert the speed of light from meters per second to nautical miles per microsecond and compare the result with the answer choices.

✅ Before You Answer

• Be sure you include the round-trip travel of the pulse (there and back), not just one-way, when relating time to distance. • Confirm your unit conversions: 1 nautical mile ≈ 1852 meters; 1 second = 1,000,000 microseconds (µs). • After deriving a value in nautical miles per microsecond, check which choice has the correct numerical size and units (µs).