What is the motional emf produced by the rod?
An emf induced by motion relative to a magnetic field is called a motional emf. This is represented by the equation emf = LvB, where L is length of the object moving at speed v relative to the strength of the magnetic field B.
How emf is produced in the rod?
Reasoning: The conducting rod is moving in a plane perpendicular to B. A motional emf is produced. The right-hand rule tells us that the magnetic force on positive charges will point in the direction away from the origin, the magnetic force on negative charges will point towards from the origin.
What is motional emf explain with diagram?
An emf induced by the motion of the conductor across the magnetic field is a motional electromotive force. The equation is given by E = -vLB. This equation is true as long as the velocity, field, and length are mutually perpendicular. The minus sign associated with the Lenz’s law.
What is the application of motional emf?
Motional emf can even be measured on airplanes. As the plane flies through the Earth’s magnetic field, an emf is induced between the wingtips. Motional emf is largest when the direction of motion of the piece of metal is perpendicular to the rod and perpendicular to the magnetic field.
What is motional emf?
Motional emf is a process in which an emf is inserted into a conductor as a result of its movement within a magnetic field. Suppose a U-shaped spinning wire is inserted into the magnetic field and a metal rod is placed over the wire.
What is mean by motional emf?
Motional emf is the emf induced in a conducting rod when it moves in a region of magnetic field. Motional emf is calculated by E=vBl. where B is the magnetic field and l is the length of the rod and v is the velocity of rod perpendicular to the length of the rod.
What is motional emf and derive its expression?
the magnetic flux ϕB enclosed by the loop PQRS. ϕB=Blx. As x is changing with time, the rate of change of flux ϕB will induce an emf given according to Faraday’s law of electromagnetic induction : ϵ=−dtdϕB=−dtd(Blx)=−Blv. This induced emf Blv is motional emf.
What is the difference between motional emf and induced emf?
By Faraday’s Law, you get an induced emf whenever there’s a changing magnetic flux through a loop. If the changing emf is due to some kind motion of a conductor in a magnetic field, you would call it a “motional emf”.
What does motional mean?
motional – of or relating to or characterized by motion.
What factors affect motional emf?
The speed at which the conductor moves through the magnetic field. The length of the conductor. The rate at which the conductor cuts the magnetic lines of force.
What is motional EMF?
Please try again later. Are you a student or a teacher? Closes this module. An emf induced by motion relative to a magnetic field is called a motional emf. This is represented by the equation emf = LvB, where L is length of the object moving at speed v relative to the strength of the magnetic field B. What is magnetic flux? What is Faraday’s law?
How to find the motional EMF of a rod?
Entering these quantities into the expression for emf yields emf = BΔA Δt = BℓΔx Δt emf = B Δ A Δ t = B ℓ Δ x Δ t. Finally, note that Δ x /Δ t = v, the velocity of the rod. Entering this into the last expression shows that is the motional emf. This is the same expression given for the Hall effect previously.
What is motional electromagnetic field?
(a) A motional emf = B ℓ v is induced between the rails when this rod moves to the right in the uniform magnetic field. The magnetic field B is into the page, perpendicular to the moving rod and rails and, hence, to the area enclosed by them. (b) Lenz’s law gives the directions of the induced field and current, and the polarity of the induced emf.
What is an emf induced by a magnetic field?
Emf induced in rod traveling through magnetic field. An emf induced by motion relative to a magnetic field is called a motional emf. This is represented by the equation emf = LvB, where L is length of the object moving at speed v relative to the strength of the magnetic field B.