Question

There is a thin metal plate having length, breadth and thickness as 2M mm, 2K mm and 1 mm respectively. If ‘N’ plates are placed one on top of the other, what is the object formed and what is its volume in $m{m}^3$?

• A. Cuboid, MKN
• B. Cuboid, 4MKN
• C. Sphere, 4MKN
• D. Cylinder, 2MKN

Answer 1

The correct option is B

Cuboid, 4MKN

Thickness of 1 plate = 1 mm.
Total thickness of N plates put together = N mm

Now, the object formed has 3 dimensions- length, breadth and thickness.

The area of one plate
$=\text{Length}\times \text{Breadth}$
$=2M\times 2K$
$=4MKm{m}^2$

The object formed when thin plates are stacked is nothing but a cuboid. This can be visualised as shown below.


$\text{Volume}=\text{Area}\times \text{Thickness}$
$=4MK\times N$
$=4MKNm{m}^3$