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Confused about mark scheme: thermal/flow rate question

Hi, confused about this marked multiple choice question. I understand the SHC equation, I understand flow rate=m/t and the rearrangement. The bit I’m confused about it that power is equated to charge over time? I’ve never seen that relationship before and I googled it and couldn’t find anywhere that suggested that P=q/t. Im really confused. Is this mark scheme correct? I thought power was work done over time.
Sorry if this is a silly question, I’m just thrown off.B8F8805A-6483-4EC7-BB49-338DCBCFE596.png
(edited 2 months ago)
Original post by Albert-
Hi, confused about this marked multiple choice question. I understand the SHC equation, I understand flow rate=m/t and the rearrangement. The bit I’m confused about it that power is equated to charge over time? I’ve never seen that relationship before and I googled it and couldn’t find anywhere that suggested that P=q/t. Im really confused. Is this mark scheme correct? I thought power was work done over time.
Sorry if this is a silly question, I’m just thrown off.B8F8805A-6483-4EC7-BB49-338DCBCFE596.png

In physics, we tend to “recycle” certain letters to mean different physical quantities. The symbol Q used here is NOT charge but “heat” or thermal energy.
In thermal physics, we tend to write Q = mcΔθ.
https://phys.libretexts.org/Bookshelves/University_Physics/Physics_(Boundless)/13%3A_Heat_and_Heat_Transfer/13.2%3A_Specific_Heat

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