NTA JEE Main 11th April 2014 Online

Three straight parallel current carrying conductors are shown in the figure. The force experienced by the middle conductor of length 25 cm is:

A coil of circular cross-section having 1000 turns and 4 cm$$^2$$ face area is placed with its axis parallel to a magnetic field which decreases by $$10^{-2}$$ Wb m$$^{-2}$$ in 0.01 s. The e.m.f. induced in the coil is:

An electromagnetic wave of frequency $$1 \times 10^{14}$$ hertz is propagating along z-axis. The amplitude of electric field is 4 V/m. If $$\varepsilon_0 = 8.8 \times 10^{-12}$$ C$$^2$$/N-m$$^2$$, then average energy density of electric field will be:

An object is located in a fixed position in front of a screen. Sharp image is obtained on the screen for two positions of a thin lens separated by 10 cm. The size of the images in two situations are in the ratio 3 : 3. What is the distance between the screen and the object?

In a compound microscope the focal length of objective lens is 1.2 cm and focal length of eye piece is 3.0 cm. When object is kept at 1.25 cm in front of objective, final image is formed at infinity. Magnifying power of the compound microscope should be:

Two monochromatic light beams of intensity 16 and 9 units are interfering. The ratio of intensities of bright and dark parts of the resultant pattern is:

A photon of wavelength $$\lambda$$ is scattered from an electron, which was at rest. The wavelength shift $$\Delta\lambda$$ is three times of $$\lambda$$ and the angle of scattering $$\theta$$ is 60°. The angle at which the electron recoiled is $$\phi$$. The value of $$\tan \phi$$ is: (electron speed is much smaller than the speed of light)

Match the List-I (Phenomenon associated with electromagnetic radiation) with List-II (Part of electromagnetic spectrum) and select the correct code from the choices given below this lists:

A radioactive nuclei with decay constant 0.5/s is being produced at a constant rate of 100 nuclei/s. If at t = 0 there were no nuclei, the time when there are 50 nuclei is:

A Zener diode is connected to a battery and a load as shown below:

The currents, I, I$$_Z$$ and I$$_L$$ are respectively.