Question

50 circular discs, each of radius 7cm and thickness 0.5cm are placed one above the other. Find the total surface area of the solid so formed. Find how much space will be left in a cubical box of side 25cm if the solid formed is placed inside it

Answer 1

Answer:

Step-by-step explanation:

Each disc has thickness of 0.5cm so 50 circular discs has height = 0.5*50 = 25cm.

Radius of each disc = 7cm

So total surface area of solid cylinder = area of top + area of bottom + lateral are;

Total surface area = 2πrh+2πr^2  (r is radius and h is height)

= 2*3.14*7*25 + 2*3.14*7*7* = 1407.43 sq. cm;

Cubical box side = 25cm;

So total volume of box = 25*25*25 = 15625;

Space left when we put the solid cylinder in that box = 15625-1407.43 = 14217.57

Answer 2

Answer:

15625-1407.43equal to 14217.53