Correct Option is (A)
Time taken to cross the field region
At the loop is inside field and flux is not changing.
1. (JEE Main 2024 (Online) 9th April Evening Shift )
A square loop of side being moved towards right at a constant speed of as shown in figure. The front edge enters the wide magnetic field at . The value of induced emf in the loop at will be :
A. zero
B. 4.5 mV
C. 0.3 mV
D. 3 mV
Correct Option is (A)
Time taken to cross the field region
At the loop is inside field and flux is not changing.
2. (JEE Main 2024 (Online) 31st January Morning Shift )
A coil is places perpendicular to a magnetic field of . When the field is changed to in , an induced emf of is produced in the coil. If the diameter of the coil is , then the number of turns in the coil is:
A. 35
B. 70
C. 7
D. 140
Correct Option is (B)
3. (JEE Main 2024 (Online) 27th January Morning Shift )
A rectangular loop of length and width is placed at to a magnetic field of . The loop is removed from the field in . The average emf induced in the loop during this time is
A. -2V
B. +2V
C. +1V
D. -1V
Correct Option is (
According to Faraday's Law of Electromagnetic Induction, the induced emf in a closed circuit is equal to the negative rate of change of magnetic flux through the circuit. Mathematically, it is expressed as:
Where is the induced emf, and is the magnetic flux.
To find the magnetic flux through the rectangular loop, we use the formula:
Where:
The area of the rectangular loop is:
Given the angle , we can calculate the initial magnetic flux :
(Since )
When the loop is removed from the magnetic field, the final magnetic flux is zero, because the loop is no longer within the magnetic field. Thus, the change in magnetic flux is:
The loop is removed from the field in seconds, so the rate of change of magnetic flux is:
Now we can find the average induced emf :
Therefore, the average induced emf in the loop during this time is . The correct answer is:
Option C
)4. (JEE Main 2024 (Online) 1st February Evening Shift)
A coil of 200 turns and area is rotated at half a revolution per second and is placed in uniform magnetic field of perpendicular to axis of rotation of the coil. The maximum voltage generated in the coil is volt. The value of is _______.
Correct answer is 5
5 (JEE Main 2024 (Online) 31st January Evening Shift)
The magnetic flux (in weber) linked with a closed circuit of resistance varies with time (in seconds) as . The induced current in the circuit at is __________ A.
Correct answer is 2