Question

class 9 ch 13 formulas​

Answer 1

Answer:

these formulas are right

Step-by-step explanation:

hope it  helps  you

Answer 2

ꜰᴀᴄᴛꜱ ᴛʜᴀᴛ ᴍᴀᴛᴛᴇʀ

• ᴛʜʀᴇᴇ ᴍᴇᴀꜱᴜʀᴇꜱ ᴏꜰ ᴄᴇɴᴛʀᴀʟ ᴛᴇɴᴅᴇɴᴄʏ ᴏꜰ ᴜɴɢʀᴏᴜᴘᴇᴅ ᴅᴀᴛᴀ ᴀʀᴇ: (ɪ) ᴍᴇᴀɴ, (ɪɪ) ᴍᴇᴅɪᴀɴ ᴀɴᴅ (ɪɪɪ) ᴍᴏᴅᴇ.

• ᴛᴏᴛᴀʟ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄᴜʙᴏɪᴅ = 2[ʟʙ + ʙʜ + ʟʜ]

• ᴛᴏᴛᴀʟ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄᴜʙᴇ = 6(ꜱɪᴅᴇ)²

• ʟᴀᴛᴇʀᴀʟ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄᴜʙᴏɪᴅ = ᴀʀᴇᴀ ᴏꜰ ᴡᴀʟʟꜱ ᴏꜰ ᴀ ʀᴏᴏᴍ = 2(ʟ + ʙ) × ʜ

• ʟᴀᴛᴇʀᴀʟ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄᴜʙᴇ = 4ᴀ²

• ᴄᴜʀᴠᴇᴅ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴄʏʟɪɴᴅᴇʀ = 2πʀʜ

• ᴛᴏᴛᴀʟ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄʏʟɪɴᴅᴇʀ = 2πʀ(ʀ + ʜ)

• ᴄᴜʀᴠᴇᴅ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄᴏɴᴇ = πʀʟ

• ᴛᴏᴛᴀʟ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄᴏɴᴇ = πʀ(ʀ + ʟ)

• ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ꜱᴘʜᴇʀᴇ = 4πʀ²

• ᴄᴜʀᴠᴇᴅ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ʜᴇᴍɪꜱᴘʜᴇʀᴇ = 2πʀ²

• ᴛᴏᴛᴀʟ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ʜᴇᴍɪꜱᴘʜᴇʀᴇ = 3πʀ²

• ᴠᴏʟᴜᴍᴇ ᴏꜰ ᴀ'ᴄᴜʙᴏɪᴅ = ʟ × ʙ × ʜ

• ᴠᴏʟᴜᴍᴇ ᴏꜰ ᴀ ᴄᴜʙᴇ = (ꜱɪᴅᴇ)²

• ᴠᴏʟᴜᴍᴇ ᴏꜰ ᴀ ᴄʏʟɪɴᴅᴇʀ = πʀ²ʀʜ

ꜱᴏʟɪᴅꜱ ᴀɴᴅ ᴛʜᴇɪʀ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀꜱ

ᴛʜᴇ ʙᴏᴅɪᴇꜱ ᴏᴄᴄᴜᴘʏɪɴɢ ꜱᴘᴀᴄᴇ ᴀʀᴇ ᴄᴀʟʟᴇᴅ ꜱᴏʟɪᴅꜱ, ꜱᴜᴄʜ ᴀꜱ ᴀ ᴄᴜʙᴏɪᴅ, ᴀ ᴄᴜʙᴇ, ᴀ ᴄʏʟɪɴᴅᴇʀ, ᴀ ᴄᴏɴᴇ, ᴀ ꜱᴘʜᴇʀᴇ, ᴇᴛᴄ.

ᴛʜᴇꜱᴇ ꜱᴏʟɪᴅꜱ ʜᴀᴠᴇ ᴘʟᴀɴᴇ ᴏʀ ᴄᴜʀᴠᴇᴅ ꜱᴜʀꜰᴀᴄᴇꜱ.

ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄᴜʙᴏɪᴅ ᴀɴᴅ ᴀ ᴄᴜʙᴇ

ᴛʜᴇ ᴏᴜᴛᴇʀ ꜱᴜʀꜰᴀᴄᴇ ᴏꜰ ᴀ ᴄᴜʙᴏɪᴅ ɪꜱ ᴍᴀᴅᴇ ᴜᴘ ᴏꜰ ꜱɪx ʀᴇᴄᴛᴀɴɢʟᴇꜱ. ɪꜰ ᴡᴇ ᴛᴀᴋᴇ ᴛʜᴇ ʟᴇɴɢᴛʜ ᴏꜰ ᴛʜᴇ ᴄᴜʙᴏɪᴅ ᴀꜱ ʟ, ʙʀᴇᴀᴅᴛʜ ᴀꜱ ʙ ᴀɴᴅ ᴛʜᴇ ʜᴇɪɢʜᴛ ᴀꜱ ʜ, ᴛʜᴇɴ

ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄᴜʙᴏɪᴅ = 2[ʟʙ + ʙʜ + ʜʟ]

ʟᴇᴛ ᴜꜱ ʀᴇᴄᴀʟʟ ᴛʜᴀᴛ ᴀ ᴄᴜʙᴏɪᴅ ᴡʜᴏꜱᴇ ʟᴇɴɢᴛʜ, ʙʀᴇᴀᴅᴛʜ ᴀɴᴅ ʜᴇɪɢʜᴛ ᴀʀᴇ ᴇQᴜᴀʟ ɪꜱ ᴄᴀʟʟᴇᴅ ᴀ ᴄᴜʙᴇ. ʟᴇᴛ ᴇᴀᴄʜ ᴇᴅɢᴇ ᴏꜰ ᴛʜᴇ ᴄᴜʙᴇ ʙᴇ �ᴀ', ᴛʜᴇɴ

ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄᴜʙᴇ = 6ᴀ2

ɴᴏᴛᴇ: ɪ. ꜱᴏᴍᴇᴛɪᴍᴇꜱ ᴀ ᴄᴜʙᴏɪᴅ ᴅᴏᴇꜱ ɴᴏᴛ ʜᴀᴠᴇ ʙᴏᴛᴛᴏᴍ ᴀɴᴅ ᴛᴏᴘ ꜰᴀᴄᴇꜱ. ɪꜱ ᴄᴀʟʟᴇᴅ ᴛʜᴇ ʟᴀᴛᴇʀᴀʟ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ.

ɪɪ. ʟᴀᴛᴇʀᴀʟ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄᴜʙᴏɪᴅ ɪꜱ 2(ʟ + ʙ)ʜ.

ɪɪɪ. ʟᴀᴛᴇʀᴀʟ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄᴜʙᴇ ɪꜱ 4ᴀ2.

ɪᴠ. ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ ᴏꜰ ᴀ ᴄᴜʙᴏɪᴅ ᴏʀ ᴄᴜʙᴇ ᴍᴇᴀɴꜱ ᴛᴏᴛᴀʟ ꜱᴜʀꜰᴀᴄᴇ ᴀʀᴇᴀ.