We read your photo as:
Mention the three states by which matter exists.
ScanSolve AI Answer
Answer
None
Step-by-step solution
3 stepsNone of the three situations result in motional emf.
Situation (a) – A positively charged dry cloth is rubbed on a piece of paper which is cut into the shape of a loop.
Rubbing produces static electric charge via friction (triboelectric effect). Placing the charged cloth near the paper loop causes electrostatic induction: opposite charges separate on the loop.
No magnetic field is present. No conductor motion in a magnetic field. No change in magnetic flux.
No motional emf ().Situation (b) – A charged loop is placed in a uniform magnetic field (into the page).
The loop is stationary. Magnetic field is static and uniform.
Magnetic flux is constant (no motion, no change in ).
Faraday's law: induced emf .
Charge on loop does not produce emf. No velocity .
No motional emf ().Situation (c) – The page (loop) on which writing is done is moving towards north.
Earth's magnetic field: horizontal component –0.4 gauss towards magnetic north; vertical component downward. Field approximately uniform over small loop.
Loop translates with velocity towards north (parallel to ).
For translational motion of rigid loop in uniform , magnetic flux constant (area and unchanged).
Motional emf (closed path, conservative field).
No motional emf ().None
Try one yourself
A new problem that tests the same skill.
Still stuck on this one?
Ask a follow-up, and the answer starts from this question.