A radio station broadcasts at 80 MHz. How long does it take for this radio signal to travel a distance of $2.0 \times 10^7 \mathrm {~m}$ through space? (c = 3.0 × 10⁸ m/s) A) 0.15 × 10^-2 s B) 15 ms C) 6.7 × 10^-2 s D) 20 ms E) 25 ms

Question

Quizplus · Accepted Answer

Use the formula: $$ ext{distance} = ext{speed} imes ext{time}$$ Rearranging to solve for time: $$ ext{time} = \frac{ ext{distance}}{ ext{speed}}$$ Plugging in the values: $$ ext{time} = \frac{2.0 imes 10^7 \mathrm {~m}}{3.0 imes 10^8\mathrm{~m/s}} = 6.7 imes 10^{-2}\mathrm{~s} = 6.7 imes 10^{-2} imes 10^3\mathrm{~ms} = 67\mathrm{~ms} $$ Therefore, the answer is C, 6.7 × 10^-2 s.

A Radio Station Broadcasts at 80 MHz 2.0×107 m2.0 \times 10^7 \mathrm {~m}2.0×107 m

A Radio Station Broadcasts at 80 MHz $2.0 \times 10^7 \mathrm {~m}$