NTA JEE Main 2nd April 2017 Offline

A magnetic needle of magnetic moment $$6.7 \times 10^{-2}$$ A m$$^{2}$$ and moment of inertia $$7.5 \times 10^{-6}$$ kg m$$^{2}$$ is performing simple harmonic oscillations in a magnetic field of 0.01 T. Time taken for 10 complete oscillations is:

In a coil of resistance 100 Ω, a current is induced by changing the magnetic flux through it as shown in the figure. The magnitude of change in flux through the coil is:

An electron beam is accelerated by a potential difference $$V$$ to hit a metallic target to produce X-rays. It produces continuous as well as characteristic X-rays. If $$\lambda_{min}$$ is the smallest possible wavelength of X-ray in the spectrum, the variation of $$\log\lambda_{min}$$ with $$\log V$$ is correctly represented in:

A diverging lens with magnitude of focal length 25 cm is placed at a distance of 15 cm from a converging lens of magnitude of focal length 20 cm. A beam of parallel light falls on the diverging lens. The final image formed is:

In a Young's double slit experiment, slits are separated by 0.5 mm, and the screen is placed 150 cm away. A beam of light consisting of two wavelengths, 650 nm and 520 nm, is used to obtain interference fringes on the screen. The least distance from the common central maximum to the point where the bright fringes due to both the wavelengths coincide is:

A particle $$A$$ of mass $$m$$ and initial velocity $$v$$ collides with a particle $$B$$ of mass $$\frac{m}{2}$$ which is at rest. The collision is head on, and elastic. The ratio of the de-Broglie wavelengths $$\lambda_{A}$$ to $$\lambda_{B}$$ after the collision is:

Some energy levels of a molecule are shown in the figure. The ratio of the wavelengths $$r = \frac{\lambda_{1}}{\lambda_{2}}$$, is given by:

A radioactive nucleus $$A$$ with a half-life $$T$$, decays into a nucleus $$B$$. At $$t = 0$$, there is no nucleus $$B$$. At some time $$t$$, the ratio of the number of $$B$$ to that of $$A$$ is 0.3. Then, $$t$$ is given by: (Consider $$\log_{e} x = \log x$$)

In a common emitter amplifier circuit using an $$n$$-$$p$$-$$n$$ transistor, the phase difference between the input and the output voltages will be:

In amplitude modulation, the sinusoidal carrier frequency used is denoted by $$\omega_{c}$$ and the signal frequency is denoted by $$\omega_{m}$$. The bandwidth $$\Delta\omega_{m}$$ of the signal is such that $$\Delta\omega_{m} \ll \omega_{c}$$. Which of the following frequencies is not contained in the modulated wave?