Question
A metal plate with a circular hole at the centre is
heated. What will happen to the area of the hole?Solution
Assuming the disc is uniform and isotropic (the same in different directions), the hole will expand in the same ratio as the metal. It is because the thermal expansion equation applies to all lengths associated with the metal, including the circumference of the hole, since the edge of the hole is made out of metal. And if the circumference of the hole expands, so does the diameter.
230 192 172 ? 122 100
...What value should come in the place of (?) in the following number series?
64, 80, 104, ?, 176, 224
97, 106, ?, 195, 411, 460
What will come in place of the question mark (?) in the following series?
29, 42, ?, 95, 135, 184
Find the missing term:
2, 6, 15, 31, 56, ?
32   48   96   ?   720   2520
82, 98, 130, 178, 242, ?
4 10 ? 62.5 156.25 390.625
...140, 146, 170, 224, ?, 470
7 47 ? 223 359 527
...
