JEE Mains · Physics · STD 12 -6. Electromagnetic induction
A coil is placed perpendicular to a magnetic field of 5000 T . When the field is changed to 3000 T in 2 s , an induced emf of 22 V is produced in the coil. If the diameter of the coil is 0.02 m , then the number of turns in the coil is _______.
- A 7
- B 70
- C 35
- D 140
Answer & Solution
Correct Answer
(B) 70
Step-by-step Solution
Detailed explanation
\(\varepsilon=N\left(\frac{\Delta \phi}{t}\right)\) \(\triangle \phi=(\triangle B) A\) \(B_i=5000 T\) \(B_f=3000 T\) \(d =0.02 m\) r = 0.01 m \(\triangle \phi=(\triangle B) A\) \(=(2000) \pi(0.01)^2=0.2 \pi\)…
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