A toy car uses a battery where 100j of chemical energy is transformed to 90j of electrical energy in a circuit, from which 75j is transformed to kinetic energy. suggest what happens to the rest of the energy supplied and find its efficiency

Efficiency = 75%

Explanation:

Step 1:

During initial transformation, 100 J of Chemical energy is transferred to 90 J of Electrical energy with a loss of 10 J due to Chemical reaction drop.

And then the Electrical form of energy is transferred into Kinetic or Mechanical energy for toy car usage. Here 15 J of energy is wasted in the form friction and Wear and Tear loss. Since Electrical to Kinetic energy conversion takes place with frictional loss .

Step 2:

So finally the available energy for usage is 75 J.

To find the efficiency the required formula is

Efficiency = (( Useful Power) / (Total Power)) * 100

                =

                = 75 %