Question

Q-8) From a solid cylinder whose height is 2.4 cm and diameter 1.4 cm , a conical cavity of the same height and same diameter is hollowed out . find the total surface area of the remaining solid to the nearest cm² .​

Answer 1

Step-by-step explanation:

Answer Answer Answer Answer

Answer 2

Step-by-step explanation:

Given:

Height (h) of the conical part = Height (h) of the cylindrical part =2.4 cm

Diameter of the cylindrical part =1.4 cm

Radius = Diameter/2

Radius(r) of the cylindrical part =0.7 cm

Slant height (l) of conical part = √r2+h2

=√(0.7)2+(2.4)2

= √0.49+5.76=√6.25=2.5cm

Total surface area of the remaining solid = CSA of cylindrical part + CSA of conical part + Area of cylindrical base

=2πrh+πrl+πr2

=2×22/7×0.7×2.4+22/7×0.7×2.5+22/7×0.7x0.7

=4.4×2.4+2.2×2.+2.2×0.7

=10.56+5.50+1.54=17.60 cm2

The total surface area of the remaining solid to the nearest cm2 is 18 cm2