Question

find the length of the longest rod that can be put it in a cubical room of length 10 m

Answer 1

$\red{hey \: mate} \\ \\ hope \: it \: helps \: you \\ \pink{the \: formula \: of \: finding \: \: diagonal \: in \: a \: cube \: \: is \: \sqrt{3}a} \\ \\ \sqrt{3} \times 10 = 10 \sqrt{3 } \\ \\ \large\bold\red{your \: ans. + solution}$

Answer 2

diagnol of a square= √[(10)^2+(10)^2]
=√100+100
=√200
=√2√100
=10√2m
diagnol of cube=√(10)^2+(10√2)^2
=√100+200
=√300
=10√3m