Physics Test 16...

Two spherical conductors A and B of radii a and b (b>a) are placed concentrically in air. The two are connected by a copper wire as shown in figure. Then the equivalent capacitance of the system is

The length of a wire of a potentiometer is 100 cm, and the e.m.f. of its standard cell is E volt. It is employed to measure the e.m.f. of a battery whose internal resistance is 0.5W. If the balance point is obtained at l = 30 cm from the positive end, the e.m.f. of the battery is

A long insulated copper wire is closely wound as a spiral of ‘ N’ turns. The spiral has inner radius ‘a’ and outer radius ‘b’. The spiral lies in the XY plane and a steady current ‘I’ flows through the wire. The Z-component of the magnetic field at the centre of the spiral is

A bar magnet of moment of inertiaplaced in a vibration magnetometer and oscillating in a uniform magnetic field makes 20 oscillations in 15 s. The magnetic moment of the bar magnet is

The loop is rotated with a constant angular speed w about an axis passing through the centre O, and perpendicular to the page. Then the induced current in the wire loop is

Which of the following electromagnetic waves has minimum frequency?

A rectangular glass slab ABCD of refractive index n1 is immersed in water of refractive index A ray of light is incident at the surface AB of the slab as shown. The maximum value of the angle of incidence max such that the ray comes out only from the other surface CD is given by

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