Physics Test 14...

In the circuit shown below, the key K is closed at t = 0. The current through the battery is

A plane electromagnetic wave travels in free space along x-axis. At a particular point in space, the electric field along y-axis is  The magnetic induction (B) along z-axis is

A lens made of glass whose index of refraction is 1.60 has a focal length of + 20 cm in air. Its focal length in water, whose refractive index is 1.33, will be

In Young's double slit experiment shown in figure S₁ and S₂ are coherent sources and S is the screen having a hole at a point 1.0mm away from the central line. White light (400 to 700nm) is sent through the slits. Which wavelength passing through the hole has strong intensity?

The maximum velocity of an electron emitted by light of wavelength λ incident on the surface of a metal of work function is

Ionization potential of hydrogen atom is 13.6eV. Hydrogen atoms in the ground state are excited by monochromatic radiation of photon energy 12.1 eV. According to Bohr’s theory, the spectral lines emitted by hydrogen will be

A working transistor with its three legs marked P, Q and R is tested using a multimeter. No conduction is found between P and Q . By connecting the common (negative) terminal of the multimeter to R and the other (positive) terminal to P or Q, some resistance is seen on the multimeter. Which of the following is true for the transistor?

What is the modulation index of an over modulated wave

In the figure shown the wave speed is v. The velocity of car is V₀. The beat frequency for the observer will be