An AC generator having 400 turns and an area of cross section of $2 \times 10^{-3} \mathrm{~m}^2$ rotates with an angular speed of $200 \pi \mathrm{rad} \mathrm{s}^{-1}$ in a uniform magnetic field of strength 0.4 T . The generator is connected to the primary of an ideal transformer having 500 turns in the primary and 2000 turns in the secondary. The secondary is connected to a $400 \Omega$ resistive load. What is the rms current in the secondary of the transformer? Assume, the transformer is ideal and the resistance of the coil is negligible
2.84 A
14.2 A
1.41 A
28.4 A
An object of mass 10 g executes SHM along the $x$-axis with frequency of $\left(\frac{10}{\pi}\right) \mathrm{Hz}$. At the point $x=2 \mathrm{~cm}$ the object has KE 1.2 J and PE 0.4 J . The amplitude of oscillation is
8 cm
4 cm
2 cm
6 cm
A circular coil of radius 7 cm and 40 turns is rotated about its vertical diameter with an angular speed of 40 radians per second in a uniform horizontal magnetic field of $4 \times 10^{-2} T$. What is the maximum current induced in the coil if the resistance of the coil is $11 \Omega$ ?
90 mA
0.9 mA
9 mA
0.09 mA
A light rod of length 1 m is suspended from ceiling horizontally by means of two vertical wires of equal length tied to its ends. One of the wires is made of material $X$ and is of cross-section $0.1 \mathrm{~cm}^2$. and the other of material Y of cross-section $0.3 \mathrm{~cm}^2 . \mathrm{A}$ weight is hung from the wire at a point to produce equal strain in the wires. The ratio of Young's moduli of wires A to B is $3: 1$. The location of the point from one end of the wire is
0.2 m
0.75 m
0.5 m
0.25 m
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