NTA JEE Main 12th April 2019 Shift 2

Consider the LR circuit shown in the figure. If the switch S is closed at t = 0 then the amount of charge that passes through the battery between t = 0 and t = $$\frac{L}{R}$$ is:

A plane electromagnetic wave having a frequency f = 23.9 GHz propagates along the positive z-direction in free space. The peak value of the Electric Field is 60 V/m. Which among the following is the acceptable magnetic field component in the electromagnetic wave?

A transparent cube of side d, made of a material of refractive index $$\mu_2$$, is immersed in a liquid of refractive index $$\mu_1$$ ($$\mu_1 < \mu_2$$). A ray is incident on the face AB at an angle $$\theta$$ (shown in the figure). Total internal reflection takes place at point E on the face BC.

Then $$\theta$$ must satisfy

A system of three polarizers P$$_1$$, P$$_2$$, P$$_3$$ is set up such that the pass axis of P$$_3$$ is crossed with respect to that of P$$_1$$. The pass axis of P$$_2$$ is inclined at 60° to the pass axis of P$$_3$$. When a beam of unpolarized light of intensity I$$_0$$ is incident on P$$_1$$, the intensity of light transmitted by the three polarizers is I. The ratio (I$$_0$$/I) equals (nearly):

Consider an electron in a hydrogen atom, revolving in its second excited state (having radius 4.65 Å). The de-Broglie wavelength of this electron is:

The electron in a hydrogen atom first jumps from the third excited state to the second excited state and subsequently to the first excited state. The ratio of the respective wavelengths, $$\frac{\lambda_1}{\lambda_2}$$, of the photons emitted in this process is:

Half lives of two radioactive nuclei A and B are 10 minutes and 20 minutes, respectively. If, initially a sample has equal number of nuclei, then after 60 minutes, the ratio of decayed numbers of nuclei A and B will be:

Figure shows a DC voltage regulator circuit, with a Zener diode of breakdown voltage = 6 V. If the unregulated input voltage varies between 10 V to 16 V, then what is the maximum Zener current?

In a CE transistor amplifier, the audio signal voltage across the collector resistance of 2 kΩ is 2 V, if the base resistance is 1 kΩ and the current amplification of the transistor is 100 then the input signal voltage is

A tuning fork of frequency 480 Hz is used in an experiment for measuring speed of sound (v) in air by resonance tube method. Resonance is observed to occur at two successive lengths of the air column, l$$_1$$ = 30 cm and l$$_2$$ = 70 cm. Then, v is equal to: