NEET 2016
For the following questions answer them individually
An electron is moving in a circular path under the influence of a transverse magnetic field of $$3.57\times10^{-2}T$$. If the value of $$\frac{e}{m}$$ is $$1.76\times10^{11}\frac{c}{kg}$$, the frequency of revolution of the electron is
Which of the following combinations should be selected for better tuning of an L-C-R circuit used for communication?
A uniform magnetic field is restricted within a region of radius r. The magnetic field changes with time at a rate $$\frac{\overrightarrow{dB}}{dt}$$. Loop 1 of radius $$R>r$$ encloses the region r and loop 2 of radius R is outside the region of magnetic field as shown in the figure below. Then the e.m.f. generated is
The potential differences across the resistance, capacitance and inductance are 80 V, 40 V and 100 V respectively in an L-C-R circuit. The power factor of this circuit is
A $$100Ω$$ resistance and a capacitor of $$100Ω$$ reactance are connected in series across a 220 V source. When the capacitor is 50% charged, the peak value of the displacement current is
Two identical glass $$(\mu_{g}=\frac{3}{2})$$ equiconvex lenses of focal length f each are kept in contact. The space between the two lenses is filled with water $$(\mu_{w}=\frac{4}{3})$$. The focal length of the combination is
An air bubble in a glass slab with refractive index 1.5 (near normal incidence) is 5 cm deep when viewed from one surface and 3cm deep when viewed from the opposite face. The thickness (in cm) of the slab is
The interference pattern is obtained with two coherent light sources of intensity ratio n. In the interference pattern, the ratio $$\frac{I_{max}-I_{min}}{I_{max}+I_{min}}$$ will be
A person can see clearly objects only when they lie between 50 cm and 400 cm from his eyes. In order to increase the maximum distance of distinct vision to infinity, the type and powerof the correcting lens, the person has to use, will be
A linear aperture whose width is 0.02 cm is placed immediately in front of a lens of focal length 60cm. The aperture is illuminated normally by a parallel beam of wavelength $$5\times10^{-5}$$ cm. The distance of the first dark band of the diffraction pattern from the centre of the screen is
