Silly Science question re metal block with a hole

Hole gets bigger. I promise. I've used the effect countless times when I was a machinist to obtain shrink fits.

Roger
Roger, you are so smart! The following is the correct answer as you stated:

The answer, from Marilyn Vos Savant:

"The hole will get larger, which is why a metal lid is easier to unscrew from a glass jar after you run hot water over it. (The metal expands faster--and more--than the glass does.) You also can use the example of shrink-fitting, a process used for the long-lasting assembly of parts: The outer part is heated to enlarge it; the inner part (which is too large to fit
inside when both are at the same temperature) is inserted; and then
the outer part is returned to its original temperature, producing a
tight fit. (Depending on the situation, sometimes the inner part is
cooled instead, or both parts are treated.)

Here'a way readers can try it for themselves: Take a thin household
sponge--the kind that expands when it gets wet--and cut a round hole
in it when it's dry. Set the "Hole" plug aside. Then soak the
sponge fully and wring out the excess water. Now pass the dry plug
through the hole quicky enough so that the plug doesn't get wet too:
There's a wee bit of room to spare. (Note: If the hole were smaller,
the plug wouldn't go through at all."

---BumbleBeeBoogie