Electrical energy is used to run the fan
Here as per given condition 750 J of electrical energy is used to run the fan which is converted into Kinetic energy as 400 J
So here we can see that 350 J of energy is lost against many other type of frictional and resistive loses.
So here we can say that out of 750 J of energy only 400 J is used to run the fan and rest amount of energy is lost against friction.
also we can say that efficiency of this fan will be



<h2>Answer: Electric energy
</h2>
Voltaic cells use chemical reactions to generate electrical energy, as well as the reverse process.
This type of cell is mainly composed of the anode (a metal electrode where oxidation occurs) and the cathode (a metal electrode where the reduction occurs). These electrodes are placed in two compartments separated by a porous plate or membrane and immersed in a medium containing ions.
This is how, <u>when the chemical reaction of oxide-reduction occurs, electricity is generated.</u>
Answer:
Reflection involves a change in direction of waves when they bounce off a barrier. Refraction of waves involves a change in the direction of waves as they pass from one medium to another.
Explanation:
Their difference lies in the prefix used before each root word, atom. The diatomic molecules are composed only of 2 atoms such as that of the diatomic elements: H2, O2, N2, Cl2, etc. On the other hand, polyatomic molecules are made up of three or mole atoms such as NH4+, H2SO4, etc.