General Science for Class 7

    Sound Waves
    One of the vibrations of the string makes
    Investigating Space
    ‘Ulysses’ has been sending information about
    Importance of Water
    The removal of salt from water on a large scale is known as
    Physical and Chemical Changes
    ‘Methane’ is an example of
    Sound Waves
    The lowest level of frequency a human ear can detect, is
    Electric Circuits and Currents
    Electricity meter records the amount of
    Sound Waves
    The microphone changes the sound waves into
    Sound Waves
    When the hand bell stimulates air particles,
    Elements and Compounds
    ‘Water’ is a
    Mixtures
    To separate different constituents with different boiling points into fractions there is use of