A coil of resistance 400 Ω is placed in a magnetic field. If the magnetic flux φ (Wb) linked with the coil varies with time t (sec) as φ = 50t² + 4. The current in the coil at t = 2 sec is (a) 0.5 A (b) 0.1 A (c) 2 A (d) 1 A

Answer: (a). |e| = (dφ)/(dt) = 100t; at t = 2 s, |e| = 200 V I = (200)/(400) = 0.5 A So the answer is (a) 0.5 A.

A coil of resistance 400 Ω is placed in a magnetic field. If the… | NEET 2012 (AIPMT, Prelims)

Q79NEET 2012 · AIPMT · PRELIMSEasy

Magnetic Flux & Faraday's Law

A coil of resistance 400 $\Omega$ is placed in a magnetic field. If the magnetic flux $\phi$ (Wb) linked with the coil varies with time t (sec) as $\phi = 50t^{2} + 4$ .

The current in the coil at t = 2 sec is

Show answer and solution

Answer: (a)

$|e| = \frac{d\phi}{dt} = 100t$ ; at $t = 2$ s, $|e| = 200$ V
$I = \frac{200}{400} = 0.5$ A
So the answer is (a) 0.5 A.

Report a mistake

More questions on Magnetic Flux & Faraday's Law

In a coil of resistance 10 Ω, the induced current developed by changing magnetic flux…NEET 2012 (AIPMT, Mains)
A conducting circular loop is placed in a uniform magnetic field, B = 0.025 T with its…NEET 2010 (AIPMT, Prelims)
A conducting circular loop is placed in a uniform magnetic field 0.04 T with its plane…NEET 2009 (AIPMT)
A circular disc of radius 0.2 meter is placed in a uniform magnetic field of induction…NEET 2008 (AIPMT)
The flux linked with a coil at any instant 't' is given by φ = 10t² - 50t + 250 The…JEE Main 2006 (AIEEE)
A coil having n turns and resistance RΩ is connected with a galvanometer of resistance…JEE Main 2004 (AIEEE)
The magnetic flux through a circuit of resistance R changes by an amount Δφ in a time Δ…NEET 2004 (AIPMT)
A rectangular coil of 20 turns and area of cross-section 25 sq. cm has a resistance of…NEET 1992 (AIPMT)

Magnetic Flux & Faraday's Law question from NEET 2012 (AIPMT, Prelims)

More questions on Magnetic Flux & Faraday's Law