Plastic drum of cylindrical shape is made by melting spherical solid plastic balls of radius 1cm . Find the number of balls required to make the drum of thickness 2 cm , height is 90 cm and outer radius is 30 cm . ( Drum has no led)

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Solution

Vol.of cylinder=πr²h
=(22/7)(30²)90
=254571.43
Vol.of inner cylinder=πr²h
=(22/7)(28^7)88
=216832
Vol.of cylinder=vol.of outer cylinder-vol.of inner cylinder
=254571.43-216832
=37739.43 cm³
Vol.of 1 ball=(4/3)(22/7)1³
=4.1905
No.of ball required =37739.43/4.1905
=9006 balls

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Plastic drum of cylindrical shape is made by melting spherical solid plastic balls of radius 1cm . Find the number of balls required to make the drum of thickness 2 cm , height is 90 cm and outer radius is 30 cm . ( Drum has no led)

Vol.of cylinder=πr²h =(22/7)*(30²)*90 =254571.43 Vol.of inner cylinder=πr²h =(22/7)*(28^7)*88 =216832 Vol.of cylinder=vol.of outer cylinder-vol.of inner cylinder =254571.43-216832 =37739.43 cm³ Vol.of 1 ball=(4/3)*(22/7)*1³ =4.1905 No.of ball required =37739.43/4.1905 =9006 balls

Vol.of cylinder=πr²h
=(22/7)(30²)90
=254571.43
Vol.of inner cylinder=πr²h
=(22/7)(28^7)88
=216832
Vol.of cylinder=vol.of outer cylinder-vol.of inner cylinder
=254571.43-216832
=37739.43 cm³
Vol.of 1 ball=(4/3)(22/7)1³
=4.1905
No.of ball required =37739.43/4.1905
=9006 balls