NTA JEE Main 10th April 2019 Shift 1

A transformer consisting of 300 turns in the primary and 150 turns in the secondary gives output power of 2.2 kW. If the current in the secondary coil is 10 A, then the input voltage and current in the primary coil are:

Given below in the left column are different modes of communication using the kinds of waves given in the right column.
(1) Optical Fibre Communication    (P) Ultrasound
(2) Radar                                          (Q) Infrared Light
(3) Sonar                                           (R) Microwaves
(4) Mobile Phones                            (S) Radio Waves
From the options given below, find the most appropriate match between entries in the left and the right column.

The electric field of a plane electromagnetic wave is given by
$$\vec{E} = E_0 \hat{i}\cos(kz)\cos(\omega t)$$
The corresponding magnetic field $$\vec{B}$$ is then given by:

A ray of light AO in vacuum is incident on a glass slab at angle 60° and refracted at angle 30° along OB as shown in the figure. The optical path length of light ray from A to B is:

One plano-convex and one plano-concave lens of the same radius of curvature R but of different materials are joined side by side as shown in the figure. If the refractive index of the material of 1 is $$\mu_1$$ and that of 2 is $$\mu_2$$, then the focal length of the combination is:

In a photoelectric effect experiment, the threshold wavelength of light is 380 nm. If the wavelength of incident light is 260 nm, the maximum kinetic energy of emitted electrons will be
Given E (in eV) = $$\frac{1237}{\lambda(\text{in nm})}$$

Two radioactive materials A and B have decay constants $$10\lambda$$ and $$\lambda$$, respectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of A to that of B will be 1/e after a time:

An NPN transistor operates as a common emitter amplifier, with a power gain of 60 dB. The input circuit resistance is 100 Ω and the output load resistance is 10 kΩ. The common emitter current gain β is:

A message signal of frequency 100 MHz and peak voltage 100 V is used to execute amplitude modulation on a carrier wave of frequency 300 GHz and peak voltage 400 V. The modulation index and difference between the two side band frequencies are:

In a meter bridge experiment, the circuit diagram and the corresponding observation table are shown in figure.

S. No.   R(Ω)       l(cm)
1.        1000         60
2.        100          13
3.        10            1.5
4.        1              1.0

Which of the reading is inconsistent?