MCQ
The wavelength of the wave is.
- A$3.5m$
- B$5.5m$
- ✓$7.5m$
- D$9.5m$
✓
Answer
Correct option: C.
$7.5m$
Using $\text{v}=\text{v}\lambda$ where $v$ is the speed of $EM$ wave.
As $\text{V}=\text{c}=3\times\frac{10\text{m}}{\text{s}}$
$\Rightarrow3\times10^8=40\times10^6\lambda$
$\Rightarrow\lambda=7.5\text{m}$
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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