A radar signal is beamed towards a planet from earth and its echo is received seven minutes later. If distance between the planet and earth is 6.3 x 10^10m then velocity of the signal will be:
Correct answer: A. 3 x 10^8 m/s
- A. 3 x 10^8 m/s
- B. 2.97 x 10^6 m/s
- C. 3.10 x 10^5 m/s
- D. 300 m/s
Explanation
To find the velocity of the radar signal, first calculate the total distance it covers by considering the round trip. The distance to the planet is 6.3x1010 m, so the total distance is twice that. The time taken for the round trip is 7 minutes, which should be converted to seconds (7 minutes = 420 seconds). The velocity is then found by dividing the total distance by the total time: Velocity = (2 x 6.3x1010 m) / 420 s = 3x108 m/s. Incorrect options result from errors in understanding the distance traveled or incorrect time conversion.
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