bhandariavi
13 disc-shaped objects (height 12/13 cm) are to be stacked in a rectangular box with horizontal dimensions (5 x 5cm). If the edges of the box contact the edges of the stack (so that there are no extra gaps) and the height of the stack and the box are exactly equal, approximately how much fluid gel can be injected into the remaining space?
A 60cm3
B 65cm3
C 70cm3
D 75cm3
E 80cm3
It is a cylinder inserted in a rectangular box.
Dimension of the rectangular box:
l=5
w=5
h=13*(12/13)=12
Total Volume = l*b*h = 25*12
Dimension of the inserted cylinder:
r = (5/2). Please see the attached image providing a top view of the box. As the lateral edges of the box touch the circle and appear as tangent to the circle. The length and width of the rectangle become equal to diameter of the circle.
h = 13*(12/13)=12
Volume occupied \(\pi*r^2*h = \frac{22}{7}*(\frac{5}{2})^2*12= \frac{22}{7}*\frac{25}{4}*12\)
Volume left for the gel = Total Volume of the box - Volume occupied by cylinder\(25*12 - \frac{22}{7}*\frac{25}{4}*12 = 25*12(1-\frac{22}{28})\)
\(25*12*\frac{6}{28}=\frac{450}{7}=64.2 \approx 65\)
Ans: "B"
Attachments
disks_in_a_box.PNG [ 5.73 KiB | Viewed 4399 times ]