Physics If n division of main scale coincides with n 1 divisions of vernier scale Given one main scale division is equal to a units Find the least count of the vernier Find the focal length of the lens shown in the figure The radii of curvature of both the surfaces are equal to R A particle of mass m moving in a circular path of radius R with a constant speed v is located at point 2R 0 at time t 0 and a man starts moving with a velocity v along the ve y axis from origin at time t 0 Calculate the linear momentum of the particle w r t the man as a function of time Hi H H Frequency of a photon emitted due to transition of electron of a certain element from L to K shell is found to be 4 2 x 10 Hz Using Moseley s law find the atomic number of the element given that the Rydberg s constant R 1 1 x 10 m R An insulated container containing mono atomic gas of molar mass m is moving with a velocity ve If the container is suddenly stopped find the change in temperature How a battery is to be connected so that the shown rheostat will behave like a potential divider Also indicate the points about which output can be taken Charges q and q are located at the corners of a cube of side a as shown in the figure Find the work done to separate the charges to infinite distance He H He A tuning fork of frequency 480 Hz resonates with a tube closed at one end of length 18 cm and diameter 5 cm in fundamental mode Calculate velocity of sound in air D ww R 44 A radioactive sample emits n 8 particles in 2 sec In next 2 sec it emits 0 75 n particle what is the mean life of the sample In a photoelectric experiment set up photons of energy 5 eV falls on the cathode having work function 3 eV a If the saturation current is i 4 A for intensity 10 W m then plot a graph between anode potential and current h Also draw a graph