Question

Can anybody tell me how to remember formula's of chapter surface area and volume​

Answer 1

the chapter consists of many formula of shapes like cone, sphere, hemisphere, cube and all.

Best way to learn it to revise and write separately.

hope it help

Answer 2

No need to learn

just u should know the concept

Like CSA of cylinder= 2 pie r h

its because curcumference of cross sectional circle × height

As circumference is 2 pie r

So its 2 pie r h

whereas its volume is pie r^2 h

because volume = area × height

Area = pie R^2

therefore volume = pie r^2 h

For cone its just 1/3 of volume of cylinder

As it is cut in 3 parts

CSA of cone = pie r l

Its because cone has variable cross section

So u have to integrate by taking small dA area of dx width and then integrate

Same why Volume of Sphere = 4/3 pie r^3

Here As Sphere contains variable cross sectional rings.

therefore u have to integrate

its Surface area = 4 pie r^2

Just learn it in a way = (2 pie r) ( 2r)

Take circumference of cross sectional passing through diameter and height takes diameter


This way u can learn