Physics Test 171

For the circuit shown in figure, which of the following statements is true?

Product of conductivity and resistivity of a metallic conductor depends on

The magnetic field of earth at the equator is approximately T. The radius of earth is Then the dipole moment of the earth will be nearly of the order of:

A thin semicircular conducting ring of radius R is falling with its plane vertical in a horizontal magnetic induction B. At the position MNQ, the speed of the ring is V and the potential difference developed across the ring is

A coil has resistance 30 ohm and inductive reactance 20 ohm at 50 Hz frequency. If an ac source, of 200 volt, 100 Hz, is connected across the coil, the current in the coil will be

Out of the following options which one can be used to produce a propagating electromagnetic wave?

Two plano-concave lenses (1 and 2) of glass of refractive index 1.5 have radii of curvature 25 cm and 20 cm. They are placed in contact with their curved surface towards each other and the space between them is filled with liquid of refractive index 4/3. Then the combination is

Two coherent point sources S₁ and S₂ are separated by a small distance d as shown. The fringes obtained on the vertical screen will be