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Prove theoretically (electromagnetic induction) `e = (dphi)/(dt)`
Concept: Electromagnetic Induction
With the help of a neat diagram, describe the construction and working of van de Graff generator.
Concept: Van-deGraaff Generator
The energy density at a point in a medium of dielectric constant 6 is 26.55 × 106 J/m3. Calculate electric field intensity at that point. (ε0 = 8.85 × 10−12 SI units).
Concept: Energy Density of a Medium
If ‘R’ is the radius of dees and ‘B’ be the magnetic field of induction in which positive charges (q) of mass (m) escape from the cyclotron, then its maximum speed (vmax) is _______.
A) `(qR)/(Bm)`
B)`(qm)/(Br)`
C) `(qBR)/m`
D) `m/(qBR)`
Concept: Electromagnetic Induction
A transformer converts 240 V AC to 60 V AC. The secondary has 75 turns. The number of turns in primary are _______.
(A) 600
(B) 500
(C) 400
(D) 300
Concept: Transformers
Define coefficient of mutual induction.
Concept: Inductance >> Mutual Inductance
Explain the phenomenon of mutual induction.
Concept: Inductance >> Mutual Inductance
Write the SI unit and dimention of of co-efficient of self induction
Concept: Inductance >> Self Inductance
Electric intensity outside a charged cylinder having the charge per unit length 'λ' at a distance from its axis is ________.
(a) E = `(2pi in_0 lambda)/(Kr^2)`
(b) E = `(in_0 lambda)/(2piKr^2)`
(c) E = `lambda/(2piin_0Kr)`
(d) E = `(4piin_0lambda)/(Kr^2)`
Concept: Applications of Gauss' Theorem > Electric Field due to a Point Charge
The electric field intensity outside the charged conducting sphere of radius ‘R’, placed in a medium of permittivity ∈ at a distance ‘r’ from the centre of the sphere in terms of surface charge density σ is
Concept: Applications of Gauss' Theorem > Electric Field due to a Point Charge
Define the capacitance of a capacitor and its SI unit.
Concept: The Parallel Plate Capacitor
A parallel plate air condenser has a capacity of 20µF. What will be a new capacity if:
1) the distance between the two plates is doubled?
2) a marble slab of dielectric constant 8 is introduced between the two plates?
Concept: The Parallel Plate Capacitor
Answer the following:
State the principles of the electric motor and electric generator.
Concept: Electromagnetic Induction
Choose the correct option:
A conductor rod of length (l) is moving with velocity (v) in a direction normal to a uniform magnetic field (B). What will be the magnitude of induced emf produced between the ends of the moving conductor?
Concept: Electromagnetic Induction
What is the energy required to build up current of 1A in an inductor of 20 mH?
Concept: Energy Stored in a Magnetic Field
In a Faraday disc dynamo, a metal disc of radius R rotates with an angular velocity ω about an axis perpendicular to the plane of the disc and passing through its center. The disc is placed in a magnetic field B acting perpendicular to the plane of the disc. Determine the induced emf between the rim and the axis of the disc.
Concept: Induced Emf in a Stationary Coil in a Changing Magnetic Field
A horizontal wire 20 m long extending from east to west is falling with a velocity of 10 m/s normal to the Earth’s magnetic field of 0.5 × 10−4 T. What is the value of induced emf in the wire?
Concept: Induced Emf in a Stationary Coil in a Changing Magnetic Field
A search coil having 2000 turns with area 1.5 cm2 is placed in a magnetic field of 0.60 T. The coil is moved rapidly out of the field in a time of 0.2 s. Calculate the induced emf in the search coil.
Concept: Induced Emf in a Stationary Coil in a Changing Magnetic Field
An aircraft of wing span of 50 m flies horizontally in the Earth's magnetic field of 6 x 10-5 T at a speed of 400 m/s. Calculate the emf generated between the tips of the wings of the aircraft.
Concept: Motional Electromotive Force (e.m.f.)
A circular coil of 100 turns with a cross-sectional area of 1 m2 is kept with its plane perpendicular to the magnetic field of 1 T. The magnetic flux linkage is ______.
Concept: Transformers
