A resistor of resistance'$R$'draws power'$P$'when connected to an AC source.If an inductance is now placed in series with $R$ ,such that the impedance of the circuit becomes'$Z$',the power drawn will be
$P\left(\frac{R}{Z}\right)$
$P\left(\frac{R}{Z}\right)^3$
$P\left(\frac{R}{Z}\right)^2$
$P \sqrt{\frac{Z}{R}}$
A simple pendulum of length $l$ has a bob of mass $m$ ,with a charge $q$ .On it a vertical sheet of charge, with surface charge density'$\sigma$'passes through the point of suspension.At equilibrium,if the string makes an angle $\theta$ with the vertical,then
$\tan \theta=\frac{\sigma q}{2 \varepsilon_0 m g}$
$\tan \theta=\frac{\sigma q}{\varepsilon_0 m g}$
$\cot \theta=\frac{\sigma q}{2 \varepsilon_0 m g}$
$\cot \theta=\frac{\sigma q}{\varepsilon_0 m g}$
The equation of a transverse wave is $y=y_0 \sin 2 \pi\left(f t-\frac{x}{\lambda}\right)$ .If the maximum particle velocity be four times that of wave velocity then
$\lambda=\frac{\pi y_0}{4}$
$\lambda=\frac{\pi y_0}{2}$
$\lambda=\pi y_0$
$\lambda=2 \pi y_0$
A uniform but time varying magnetic field is present in a circular region of radius ' $R$ '. The magnetic field is perpendicular and into the plane of loop and the magnitude of field is increasing at a constant rate $\alpha$. There is a straight conducting rod of length 2 R placed as shown in figure. The magnitude of induced emf across the rod is

$\pi \mathrm{R}^2 \alpha$
$\frac{1}{2} \pi \mathrm{R}^2 \alpha$
$\frac{1}{\sqrt{2}} \mathrm{R}^2 \alpha$
$\frac{1}{4} \pi \mathrm{R}^2 \alpha$
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