5. In amplitude modulation, sinusoidal carrier frequency used 6. is denoted by @o, and the signal frequency is denoted by co The bandwidth (A) of the signal is such that A < Which of the following frequencies is not contained in the modulated wave? (1) 0m+w (3) m (2) 0-0 (4) @ 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: (1) real and at a distance of 40 cm from the divergent lens 7. real and at a distance of 6 cm from the convergent lens (3) real and at a distance of 40 cm from convergent lens (4) virtual and at a distance of 40 cm from convergent lens. The moment of inertia of a uniform cylinder of length l and radius R about its perpendicular bisector is I. What is the ratio /R such that the moment of inertia is minimum ? (1) 1 3 (3) 3 (2) 2 3 (4) 2 8. 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 in is the smallest possible wavelength of X-ray in the spectrum, the variation of login with log V is correctly represented in: 9. log log (1) (2) log V log V log log (3) (4) log V log V A radioactive nucleus A with a half life T, decays into a nucleus B. Att=0, there is no nucleus B. At sometime t, the ratio of the number of B to that of A is 0.3. Then, t is given by (1) t=T log (1.3) T (2) t= log(1.3) (3) t=T- log 2 (4) t=T- Tlog 1.3 log 1.3 log 2 10. An electric dipole has a fixed dipole moment p, which makes angle with respect to x-axis. When subjected to an electric field E = Ei, it experiences a torque T = Ti. When subjected to another electric field E = 3E it experiences torque T = -T. The angle is: (1) 60 (3) 30 (2) 90 (4) 45 Activa Go to Se