Physics
(a) A cell is sending current in an external circuit. How does the terminal voltage compare with the emf of the cell?
(b) At what voltage is the alternating current supplied to our houses?
(c) How should the electric lamps in a building be connected?
Related Questions
(i) A wire of length 80 cm has a frequency of 256 Hz. Calculate the length of a similar wire under similar tension, which will have frequency 1024 Hz.
(ii) A certain sound has a frequency of 256 hertz and a wavelength of 1.3 m.
Calculate the speed with which this sound travels.
What difference would be felt by a listener between the above sound and another sound travelling at the same speed, but of wavelength 2.6 m?
(a) The isotope of 92U238 decays by α-emission to an isotope of thorium(Th). The thorium isotopes decays by β-emission to an isotope of protactinium (Pa). Write down the equations to represent these two nuclear charges.
(b) Calculate the numbers of α and β particles emitted.
(a) A current of 1 A flows in a series circuit having an electric lamp and a conductor of 5 Ω when connected to a 10 V battery. Calculate the resistance of the electric lamp.
(b) Now, if a resistance of 10 Ω is connected in parallel with this series combination, then what change (if any) in current flowing through 5 Ω conductor and potential difference across the lamp will take place? Give reason.
Farmers fill their fields with water on a cold winter night. Explain in brief along with a reason.