A person is going from Chennai to Pondicherry in car of 2000 kg which is moving with an average speed of 60 km/h.
What will be the approximate amount of energy recovered due to regenerative braking, if it comes to a full halt and 50% of the
energy is recovered during the braking process?
Answers
Given :
A car of mass 2000 kg is moving with the speed of 60 km/hr
50% of energy is recovered through regenerative braking if the car is stopped fully .
To Find :
Amount of energy recovered through braking
Solution :
•Mass of car is 2000 kg
initial speed = 60km/hr= 50/3 m/s
Initial kinetic energy = 1/2mv²
= 1/2×2000×(50/3)² = 1000×2500/9
= 2500000/9 J = 277777.777 J
Final speed = 0 m/s
Final kinetic energy = 0 J
•Energy applied by brakes = change in energy of car
•Energy applied = final energy-initial energy
Energy applied = 0 - 277,777.777
Energy applied = - 277,777.777 J
•where negative sign indicates energy is applied by brakes or energy is lose by car
•Now, 50% of energy applied can be recovered
So, Energy recovered = 277,777.777/2
Energy recovered = 138,888.888 J
•Hence , 138.888 KJ of energy can be recovered through regenerative braking.