Electrostatic Potential and Capacitance — Physics STD 12 Science — Question

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An unknown hot gas emits radiation of wavelengths 46.0nm, 82.8nm and 103.5nm only. Assume that the atoms have only two excited states and the difference between consecutive energy levels decreases as energy is increased. Taking the energy of the highest energy state to be zero, find the energies of the ground state and the first excited state.

Which of the following is / are true about the principle of Van de Graaff generator?

Suppose a planet goes around Sun with a linear speed twice as fast that of earth. What will be it's orbit size as compared to that of earth ? (Radius of earth = R)(a) R / 4  (b) R / 2(c) R (d) 2R

X-rays can be used to study crystal structure, if the wavelength lies in the range(a) 2 Å to 0.1 Å(b) 10 Å to 5 Å(c) 50 Å to 10 Å(d) 100 Å to 50 Å

If a charged particle kept at rest experiences an electromagnetic force:

The induction coil works on the principle of

A 500 W heating unit is designed to operate from a 115 volt line. If the line voltage drops to 110 volt, the percentage drop in heat output will be(a) 10.20%(b) 8.1%(c) 8.6%  (d) 7.6%

In a lossless transformer an alternating current of  2 amp is flowing in the primary coil. The number of turns in the primary and secondary coils are 100 and 20 respectively. The value of the current in the secondary coil is(a) 0.08 A(b) 0.4 A(c) 5 A(d) 10 A