Someone (let's call him Bob) is playing games with someone else (let's call her Alice). Bob used his shrink ray to reduce Alice in size by about 40% (for the purpose of this question, don't worry about how this was accomplished, or any of the potential physics issues).
He did this while Alice was sleeping, and then moved her.
So... Alice wakes up one morning in an unfamiliar bedroom, 60% of her former size (BTW, that's 60% height, not 60% mass). She is unaware of Bob's shrinking technology, but is predisposed to believe that Bob is pranking her by putting her in a room where everything is larger than normal. (Assume she believes that Bob has the means to accomplish this.)
Eventually, Bob is going to walk in and the jig will be up, but until then...
- Alice's body metabolism seems to be functioning normally.
- Alice's senses (sight, hearing, etc.) are not noticeably affected.
- Alice either doesn't speak, or her voice is not noticeably different.
- Alice doesn't figure it out from looking at herself.
- Alice doesn't get up off the bed before Bob arrives.
- The bedroom is clean and uncluttered (think 'magazine photo').
- There are no personal effects in evidence.
- There are no mirrors in the bedroom.
- There are light fixtures, but no visible bulbs, and no other electronics.
- There are several pieces of wood furniture (including the bed) and a chair or two.
- There are no visible clothes except what Alice is wearing.
...so Alice won't figure it out due to e.g. looking closely at something like a power plug (or smart phone) that would be difficult to fake, or noticing that the entire world (not just an immediate space that Bob might "fake") or just too many 'things' are "scaled up".
Will Alice figure out what has really happened before she sees Bob? Is it plausible that she doesn't? If she does figure it out, what gives it away? (Would the change in mass be blatantly obvious, if her muscles are also weaker?)
Alice is of sound body and mostly sound mind (above average naïvete), but for story reasons is not going to be poking around the room before Bob shows up... but this might not be for an hour (i.e. she has more than a few seconds). She will likely sit up, maybe stand, roll over, or curl up, but is not going to start doing calisthenics. She's also not going to take her clothes off. There is a window, but the view is not familiar, nor is there anything near enough to the window to make the shrinking obvious¹. She can closely inspect her clothes and the bed, and can look at other things in the room, but is inclined to believe the clothing could be a trick (coarser fabric, larger than normal thread and such).
(¹ At least, I don't think it would be obvious if all you can see is natural terrain, and that not very close by?)
Thank you everyone that answered! There are some good gems in here that I will use, however, I have ultimately decided to go with my original plan that she won't immediately figure it out (and have therefore accepted Halfthawed's answer. For my purposes, there are several reasons, including that the story circumstances are such that Alice will be less likely to notice the changes to her own body. I was looking more for some external (probably visual) hint that would give the game away, and no one (myself included) has been able to come up with one. (I'm also going to throw in something that looks "normal size" but isn't as an additional means of distracting Alice from the truth.)
Again, thank you all! This question went over much better than I was honestly expecting and the responses are of very high quality. Y'all deserve your upvotes!