An object gains excess negative charge after being rubbed
against another object, which is:
J.J Thomson observed deflection of cathode rays in:
The center of curved surface of spherical mirror is called:
To protect the gold leaves of electroscope from the external
electric disturbances, the aluminum foil is grounded by a thin wire, which is
made up of:
The waves, which are used to detect the broken bones are
called: