EASY
12th CBSE
IMPORTANT
Earn 100

A fan blade of length 2a rotates with frequency f cycles per second perpendicular to a magnetic field B. Find the p.d. between the centre and the end of the blade.

Important Questions on Electromagnetic Induction

EASY
12th CBSE
IMPORTANT
New Simplified Physics (Vol 1) For Class 12>Chapter 6 - Electromagnetic Induction>Problems For Practice>Q 12
In a ceiling fan, each blade rotates in a circle of radius 0.5 m. If the fan makes 20 revolutions per second and if the vertical component of earth’s field is 8×10−5 Wb m−2, calculate the p.d. developed between the ends of each blade.
EASY
12th CBSE
IMPORTANT
New Simplified Physics (Vol 1) For Class 12>Chapter 6 - Electromagnetic Induction>Problems For Practice>Q 13
A metal disc of radius 200 cm is rotated at a constant angular speed of 60 rad s−1 in a plane at right angles to an external field of magnetic induction 0.05 Wb m−2. Find the emf induced between the centre and a point on the rim.
EASY
12th CBSE
IMPORTANT
New Simplified Physics (Vol 1) For Class 12>Chapter 6 - Electromagnetic Induction>Problems For Practice>Q 14
A wheel with 15 metallic spokes each 60 cm long is rotated at 360 rev⁄min in a plane normal to the horizontal component of earth’s magnetic field. The angle of dip at that place is 60°. If the emf induced between rim of the wheel and the axle is 400 mV, calculate the horizontal component of earth’s magnetic field at the place. How will the induced emf change, if the number of spokes is increased?
EASY
12th CBSE
IMPORTANT
New Simplified Physics (Vol 1) For Class 12>Chapter 6 - Electromagnetic Induction>Problems For Practice>Q 1
A closely wound rectangular coil of 200 turns and size 0.3m×0.1m is rotating in a magnetic field of induction 0.005 Wb m−2 with a frequency of revolution 1800 rpm about an axis normal to the field. Calculate the maximum value of induced emf.
EASY
12th CBSE
IMPORTANT
New Simplified Physics (Vol 1) For Class 12>Chapter 6 - Electromagnetic Induction>Problems For Practice>Q 2
A rectangular coil of dimensions 0.1m×0.5m consisting of 2000 turns rotates about an axis parallel to its longer side, making 2100 revolutions per minute in a field of 0.1 T. What is the maximum emf induced in the coil? Also find the instantaneous emf, when the coil is 60° to the field.
EASY
12th CBSE
IMPORTANT
New Simplified Physics (Vol 1) For Class 12>Chapter 6 - Electromagnetic Induction>Problems For Practice>Q 3
The armature coil of a generator has 20 turns and its area is 0.127 m2. How fast should it be rotated in a magnetic field of 0.2 Wb m−2, so that the peak value of induced emf is 160 V?
EASY
12th CBSE
IMPORTANT
New Simplified Physics (Vol 1) For Class 12>Chapter 6 - Electromagnetic Induction>Problems For Practice>Q 4
A circular coil of cross-sectional area 200 cm2 and 20 turns is rotated about the vertical diameter with angular speed of 50 rad s−2 in a uniform magnetic field of magnitude 3.0×10−2 T. Calculate the maximum value of the current in the coil.
EASY
12th CBSE
IMPORTANT
New Simplified Physics (Vol 1) For Class 12>Chapter 6 - Electromagnetic Induction>Problems For Practice>Q 5
Calculate the maximum emf induced in a coil of 100 turns and 0.01 m2 area rotating at the rate of 50 rps about an axis perpendicular to a uniform magnetic field of 0.05 T. If the resistance of the coil is 30 Ω, what is the maximum power generated by it?