The frequency and work function of an incident photon are n andππ. If f0 is the threshold frequency, then necessary condition for the emission of photo electron is:
A machine gun fires βnβ bullets per second and the mass of each bullet is m. If v is the speed of each bullet then the force exerted on the machine gun is:
A man M1 of mass 80 kg runs up a staircase in 15s. Another man M2 also of mass 80 kg runs up the same staircase in 20s. The ratio of the power developed by them will be
Nuclear fission experiments show that the neutrons the uranium nuclei into two fragment
of about the same size. This process is accompanied by the emission of several:
A man weighing 500 N carries a load of 10 kg to the top of a building in 4 minutes. The work done by the man is 6 Γ ππ4 J. If he carries the same load in 8 minutes, the work done by the man will be: