Question

A solid cube of side 7 cm is melted to make a cylinder of height 5 cm find the radius of base of cylinder

Answer 1

Side of cube = 7 cm



Volume of cube = (7)³ = 343 cm³.




Height of cylinder ( H ) = 5 cm


Let radius of cylinder (R ) = x cm.



Volume of cylinder = Volume of cube



πR²H = 343

22/7 × x² × 5 = 343




X² = ( 343 × 7 )/ ( 22 × 5 )


X² = 21.82 cm



X = 4.6 cm

Answer 2

yoυr anѕwer !!

ɢɪᴠᴇɴ:

sɪᴅᴇ ᴏғ ᴄᴜʙᴇ = 7ᴄᴍ

ʜᴇɪɢʜᴛ = 5ᴄᴍ

ᴠᴏʟᴜᴍᴇ ᴏғ ᴄʏʟɪɴᴅᴇʀ = ᴠᴏʟᴜᴍᴇ ᴏғ ᴄᴜʙᴇ

ғɪɴᴅ:

ʀᴀᴅɪᴜs ᴏғ ʙᴀsᴇ ᴏғ ᴄʏʟɪɴᴅᴇʀ.

sᴏ,

$= > volume \: of \: cylinder = {side}^{3} \\ \\ = > volume \: of \: cylinder = {7}^{3} \\ \\ = > volume \: of \: cylinder = 7 \times 7 \times 7 \\ \\ = > volume \: of \: cylineder = 343 {cm}^{3}$

ᴡᴇ ᴋɴᴏᴡ ᴛʜᴀᴛ,

ᴠᴏʟᴜᴍᴇ ᴏғ ᴄʏʟɪɴᴅᴇʀ = ᴠᴏʟᴜᴍᴇ ᴏғ ᴄᴜʙᴇ

sᴏ,

$= > \pi {r}^{2} h = 343 \\ \\ = > \frac{22}{7} \times {r}^{2} \times 5 = 343 \\ \\ = > \frac{110}{7} \times {r}^{2} = 343 \\ \\ = > {r}^{2} = 343 \times \frac{7}{110} \\ \\ = > {r}^{2} = \frac{2401}{110} \\ \\ = > {r}^{2} = 21.82 \\ \\ = > {r}^{2} = {4.6}^{2} \\ \\ => r = 4.6cm$

ʜᴇɴᴄᴇ, 4.6ᴄᴍ ɪs ʏᴏᴜʀ ᴀɴsᴡᴇʀ !

тнanĸѕ !!