# Pls answer 25th ques I didn't get this

In image attached by you it is not mentioned which is Q25. So I am solving the first question given in image.

${\mu}_{r}=1.3\phantom{\rule{0ex}{0ex}}{\epsilon}_{r}=2.14\phantom{\rule{0ex}{0ex}}Speedofelectromagneticwavesis\phantom{\rule{0ex}{0ex}}v=\frac{1}{\sqrt{{\epsilon}_{r}{\epsilon}_{o}{\mu}_{r}{\mu}_{o}}}\phantom{\rule{0ex}{0ex}}asc=\frac{1}{\sqrt{{\epsilon}_{o}{\mu}_{o}}}\phantom{\rule{0ex}{0ex}}hencev=\frac{c}{\sqrt{{\epsilon}_{r}{\mu}_{r}}}\phantom{\rule{0ex}{0ex}}\therefore v=\frac{(3\times {10}^{8})}{\sqrt{(1.3\times 2.14}}=1.79\times {10}^{8}m/s$

Regards

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