Physics - Study Mode
[#661] Kinetic energy depends on
Correct Answer
(D) Both mass and velocity of the moving body
Explanation
Solution: Kinetic energy depends on both mass and velocity of the moving body.
[#662] The device used to convert solar energy into electricity is
Correct Answer
(A) Photovoltaic cell
Explanation
Solution: A photovoltaic cell, commonly called a solar cell or PV, is the technology used to convert solar energy directly into electrical power. A photovoltaic cell is a non-mechanical device usually made from silicon alloys. Sunlight is composed of photons, or particles of solar energy.
[#663] Magnetism in materials is due to
Correct Answer
(B) Circular motion of electrons
Explanation
Solution: Magnetism is caused by the motion of electric charges.
[#664] The method of magnetisation is:
Correct Answer
(A) Hammering a magnet
Explanation
Solution: Hammering a rod will either allow it to become slightly magnetic if laid along a magnetic field (i.e.North - South) or demagnetise it if laid across the field lines (i.e. East-West). A current passing through a coil will produce a magnetic field.
[#665] Magnetic keepers are pieces of
Correct Answer
(D) Soft iron
Explanation
Solution: Magnetic keepers are pieces of soft iron that are placed across the poles of a bar magnet or a horseshoe magnet. They help prevent the loss of magnetism.