Catalysts
a catalyst is something added to a reaction that speeds it up (or lowers the activation energy)
increasing the temp would speed up the whole reaction but not lower the activation energy
so B.
The answer is the option c. generator. Generator is a machine that
converts mechanical energy into electricity. The way it is made is
because the mechanical movement may be transformed in rotation of
magnets placed inside a coiled wire, and this induces the movement of
electrons through the coiled wire. As you know electricity is the flow
of electrons.
Answer:
Explanation:
Potential energy on the surface of the earth
= - GMm/ R
Potential at height h
= - GMm/ (R+h)
Potential difference
= GMm/ R - GMm/ (R+h)
= GMm ( 1/R - 1/ R+h )
= GMmh / R (R +h)
This will be the energy needed to launch an object from the surface of Earth to a height h above the surface.
Extra energy is needed to get the same object into orbit at height h
= Kinetic energy of the orbiting object at height h
= 1/2 x potential energy at height h
= 1/2 x GMm / ( R + h)
