Which of the following i. \(\beta\)-particles ii. protons iii. neutrons iv. \(\alpha\)-particles. may be found in light nuclei?

Radio waves have a velocity of 3 x 10⁸ms^-1. A radio station sends out a broadcast on a frequency of 800kHz. The wavelength of the broadcast is

What is the cost of running five 50W lamps and four 100W lamps for 10 hours if electrical energy costs 2 kobo per kWh?

Which of the following statements is (are) NOT true about the emission of the photoelectrons from metallic surfaces?

i. all metallic surfaces emits the same number of photoelectrons in a given light

ii. most metallic surfaces emit the same number of photoelectrons in visible and infra-red light

iii. a metallic surface emits photoelectrons only if the frequency of the incident light is higher than its own characteristics threshold frequency