MCQ
The wavelength of the wave is.
- A3.5m
- B5.5m
- C7.5m
- D9.5m
✓
Answer
- 7.5m
Explanation
Using $\text{v}=\text{v}\lambda$ where v is the speed of EM wave.
As $\text{V}=\text{c}=3\times\frac{10\text{m}}{\text{s}}$
$\Rightarrow3\times10^8=40\times10^6\lambda$
$\Rightarrow\lambda=7.5\text{m}$
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