Question

A radar sends a signal to an aircraft at a distance of 30 km away and received it back after 2×10^-4 seconds. What is the speed of the signal?​

Answer 1

$\huge{\underline{\boxed{\sf{\red{\mathfrak{Solution-}}}}}}$

• $\sf{Total\:distance\:travelled=2 × 30 km}$

$\sf\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:{= 60 km = 6 × 10^4 m}$

• Time taken $\sf{=2×10^{-4}s}$

$\sf{∴Speed\:of\:the\:signal=\dfrac{(6×10^4)m}{(2×10^{-4})s}}$

$\sf\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:={\red{3 × 10^8 m/s.}}$

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