19.
20. Volume of a right circular cylinder is 44 cm! Calculate its total surface area if its diameter is
7 cm.
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Answers
Answer:
volume of a right circular cylinder is 44 CM calculate its total surface area if its diameter is 7 cm
Answer:
The circumference of the cylinder base is
= ( 2 )*(pi)*( r ) cm where r = radius of the circular base.
That is ( 2 )(pi)( r ) = ( 44 )cm or
( radius ) = [ (44/((2)(pi)) ] = ( 7.0064 )cm.
I have approximated ( pi ) as ( 3.14 ) for this calculation.
Area of the cylindrical base is ( pi )*( radius )^2
Therefore area of base
= ( 3.14 )*( 7.0064 )^2 =( 154.1415 )cm squared.
Volume of Cylinder
Volume = Atea of base multiplied by cylinder height or
= ( 154.1415 ) * ( 7 )
= ( 1079.0 ) cubic centimetres approximately with some slight loss in accuracy due to rounding of pi.
Lateral Surface Area
The lateral surface area = circumference of the cylindrical base multiplied by the height of the cylinder.
= ( 44 )*( 7 ) = ( 308 ) cm squared
Inherent Assumption
It is assumed that the thickness of the cylinder material is small and the cylinder doesn't overlap the area of the base. If it did, the lateral surface area calculated here might be understated slightly.