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motional emf and induced emf in rotating rod questions with solutions
Practice Electromagnetic Induction for JEE Main, JEE Advanced, NEET, and Classes 11–12. Attempt each question, then open it for the full solution.
Showing 1–10 of 13 questions
- MCQmediumElectromagnetic Induction
A 20 m long uniform copper wire held horizontally is allowed to fall under the gravity (g = 10 m/s²) through a uniform horizontal magnetic field of 0.5 Gauss perpendicular to the length of the wire. The induced EMF across the wire it travells a vertical distance of 200 m is _____ mV.
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JEE Mains 202623 January Morning Shift
Open question & full solution → - IntegermediumElectromagnetic Induction
A 20 cm metallic rod rotates at 210 rpm about an axis through one end, normal to the rod. A uniform magnetic field B = 0.2 T is parallel to the axis. Find the emf between the centre and the outer ring, in mV. Take π = 22/7.
15 April 2023 Morning Shift
Open question & full solution → - NumericmediumElectromagnetic Induction
A ceiling fan having 3 blades of length 80 cm each is rotating with an angular velocity of 1200 rpm. The magnetic field of earth in that region is 0.5 G and angle of dip is 30º. The emf induced across the blades is Nπ × 10⁻⁵ V. The value of N is _____ .
JEE Mains 2024 30 Jan Morning Shift
Open question & full solution → - NumericeasyElectromagnetic Induction
A rod of length 60 cm rotates with a uniform angular velocity 20 rad s⁻¹ about its perpendicular bisector, in a uniform magnetic field 0.5 T. The direction of magnetic field is parallel to the axis of rotation. The potential difference between the two ends of the rod is ______ V.
JEE Mains 2024 04 Apr Evening Shift
Open question & full solution → - MCQmediumElectromagnetic Induction
A conducting rod of length L rotates in its own plane about one end with constant angular speed ω. A magnetic field perpendicular to the plane of rotation varies with radial distance r as B(r) = B₀ exp(-λr), where λ is a positive constant. Neglect the centripetal force on electrons in the rod. Which expression gives the motional emf between the ends of the rod?
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JEE Mains 2026 5 April Evening Shift
Open question & full solution → - MCQmediumElectromagnetic Induction
A 1 m long metal rod AB completes the circuit as shown in figure. The area of circuit is perpendicular to the magnetic field of 0.10 T. If the resistance of the total circuit is 2Ω then the force needed to move the rod towards right with constant speed (v) of 1.5 m·s⁻¹ is ________ N.
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JEE Mains 202621 January Morning Shift
Open question & full solution → - NumericeasyElectromagnetic Induction
A horizontal straight wire 5 m long extending from east to west falling freely at right angle to horizontal component of earth’s magnetic field 0.60 × 10⁻⁴ Wbm⁻². The instantaneous value of emf induced in the wire when its velocity is 10 ms⁻¹ is _________ × 10⁻³ V.
JEE Mains 2024 29 Jan Evening Shift
Open question & full solution → - IntegermediumElectromagnetic Induction
A conductor wire ABCDE, with each arm 10 cm long, is placed in a magnetic field B = 1/√2 T perpendicular to its plane, as shown in the original figure. The conductor is pulled to the right with constant speed 10 cm/s. The induced emf between points A and E is ______ mV.
JEE Mains 2025 4 April Morning Shift
Open question & full solution → - MCQmediumElectromagnetic Induction
A metallic rod of length 'L' is rotated with an angular speed of ‘ω’ normal to a uniform magnetic field 'B' about an axis passing through one end of rod as shown in figure. The induced emf will be :
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JEE Mains24 January 2023Shift 2Evening Shift
Open question & full solution → - IntegereasyElectromagnetic Induction
A metallic cube of side 15 cm moves along +y at 2 m s⁻¹ in a uniform magnetic field 0.5 T along +z. The equilibrium potential difference between the higher- and lower-potential faces is ______ mV.
JEE Mains11 April 2023Shift 2Evening Shift
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