Machine-translated by Google. Questions are authored in English.
Top

Discussion

Two circular cylinders of equal volume have their heights in the ratio 1: 2. Ratio of their radii is

  • A.(1:2)
  • B.(√2:1)
  • C.(2:1)
  • D.(√3:2)

Answer: B

Equal volumes with heights in the ratio \( 1 : 2 \):

\[ \pi r_{1}^{2} h = \pi r_{2}^{2} (2h) \]

\[ r_{1}^{2} = 2 r_{2}^{2} \quad\Longrightarrow\quad \frac{r_{1}}{r_{2}} = \sqrt{2} \]

So the ratio is \( \sqrt{2} : 1 \). The shorter cylinder must be wider, and because volume depends on \( r^{2} \), halving the height needs only a \( \sqrt{2} \) increase in radius rather than a doubling.

No comment is present. Be the first to comment.
Loading…

Post your comment

Please log in or register to post a comment.