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.
A certain sound has a frequency of 256 hertz and a wavelength of 1.3 m.
1. Calculate the speed with which this sound travels
2. 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?
Name the colour code of the wire which is connected to the metallic body of an appliance.
To which wire of a cable in a power circuit should the metal case of geyser be connected.
Answer the following questions based on a hot cathode ray tube.
(i) Name the charged particles
(ii) State the approximate voltage used to heat the filament
(iii) What will happen to the beam when it passes through the electric field?
State three factors on which the rate of emission of electrons from a metal surface depends?
What are free electrons?
The electrons in the outer shells (valence electrons) are loosely bound to
the atoms, hence they are free to move easily within the metal surface but cannot leave the metal surface. Such electrons are called free electrons.