Physics Test 15...

A ray of light is incident at an angle of 60° on one face of a prism of angle 30°. The emergent ray of light makes an angle of 30° with incident ray. The angle made by the emergent ray with second face of prism will be :-

The focal length of a convex lens of glass (µ = 1.5) is 2 cm. The focal length of the lens when immered in a liquid of refractive index 1.25 will be 

An observer is moving with half the speed of light towards a stationary microwave source emitting waves at frequency 10 GHz. What is the frequency of the microwave measured by the observer? (speed of light = 3 × 10⁸ ms^–1)

Two Polaroids P₁ and P₂ are placed with their axis perpendicular to each other. Unpolarised light I₀ is incident on P₁. A third polaroid P₃ is kept in between P₁ and P₂ such that its axis makes an angle 45° with that of P₁. The intensity of transmitted light through P₂ is :-

A point charge q is placed at center of a spherical shell of radius . Electric flux through a position of sphere having surface area = 0.2 m² is :

A rigid container with thermally insulated walls contains a coil of resistance 100Ω, carrying current 1A. Change in energy after 5 min will be :

Evaluate the induced emf (in μV) in the loop if the long wire carries a current of 50 A and the loop has a instantaneous velocity v = 10 m/sec at the location x = 0.2 m as shown in fig. (a = 0.1 m)

A hollow cyclindrical wire carries a current I, having inner and outer radii 'R' & '2R' respectively. Magnetic field at a point which 3R/2 distance away from its axis is :

A series AC circuit containing an inductor (20 mH), a capacitor (120 mF) and a resistor (60Ω) is driver by an AC source of 24V/50Hz. The energy dissipated in the circuit in 60 S is nearest to :

In a photoelectric emission, electrons are ejected from metals X and Y by light of frequency f. The potential difference V required to stop the electrons is measured for various frequencies. If Y has a greater work function than X, which graph illustrates the expected results :-