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GUJCET · Physics · Electromagnetic Waves
If the Wave length of light is 4000Å, then the number of waves in 1 mm length will be __________ -
- A 25
- B 2500
- C 250
- D 25000
Answer & Solution
Correct Answer
(B) 2500
Step-by-step Solution
Detailed explanation
(B) 2500
Number of waves
\(
\begin{aligned}
& =\frac{1}{\lambda} \\
& =\frac{10^{-3}}{4000 \times 10^{-10}} \\
& =0.25 \times 10^{4} \\
& =2500
\end{aligned}
\)
Number of waves
\(
\begin{aligned}
& =\frac{1}{\lambda} \\
& =\frac{10^{-3}}{4000 \times 10^{-10}} \\
& =0.25 \times 10^{4} \\
& =2500
\end{aligned}
\)
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