Physics Test - ...

There is a stream of neutrons with a kinetic energy of 0.0327 eV. If the half life of neutron is 700 second, what fraction of neutrons will decay before they travel a distance of 10 m? Given mass of neutron = 1.675 × 10^–27 kg.

A straight segment OC of length L metre of a circuit carrying a current I amp is placed along the x-axis. Two infinitely long straight wires A and B, each extending from z = -∞, are to + ∞ are fixed at y = -a metre and each carry a current I amp. Into plane of the paper. Obtain the expression for the force acting on the segment OC.

Ultraviolet beam of wavelength 280 nm is incident on lithium surface of work function 2.5 eV. The maximum velocity of electron emitted from metal surface is.......(Mass of electron is 9.1 x 10^-31 kg)

Two microwave coherent point sources emitting waves of wavelengths λ are placed at 5λ distance apart. The interference is being observed on a flat non-reflecting surface along a line passing through one source, in a direction perpendicular to the line joining the two sources (refer figure) Considering λ as 4mm, calculate the positions of maxima. Take k initial phase difference between the two sources to be zero.

An open pipe is suddenly closed at one end with the result that the frequency of third harmonic of the closed pipe is found to be higher by 100 Hz than the fundamental frequency of the open pipe. The fundamental frequency of the open pipe is

Calculate the magnetic field induction at the centre of a hydrogen atom caused by an electron moving along the first Bohr orbit.

Two charges q₁ and q₂ are placed 30 cm apart, as shown in the figure. A third charge q₃ is moved along the arc of a circle of radius 40cm from C to D. The change in the potential energy of the system is q₃/4πε₀k , where k is

A bead of mass m is located on a parabolic wire with its axis vertical and vertex at the origin as shown in figure and whose equation is x² = 4ay. The wire frame is fixed and the bead can slide on it without friction. The bead is released from the point y = 4a on the wire frame from rest. The tangential acceleration of the bead when it reaches the position given by y = a is :

A gas under constant pressure of 4.5 x 10⁵ Pa when subjected to 800 kJ of heat, changes the volume from 0.5 m³ to 2.0 m³. The change in internal energy of the gas is

A particle executes simple harmonic motion with a frequency f​. The frequency with which the potential energy oscillates is