PG Diploma EV– Semester 1 Paper 2

Question Bank – Section C

50 Numericals with Answers

1. A battery pack has 400 V and 50 Ah. Calculate energy in kWh.

Answer:
Energy = V × Ah = 400 × 50 = 20000 Wh = 20 kWh

2. An EV battery capacity is 60 kWh. Charger power is 10 kW. Find charging time.

Answer:
Time = Energy / Power = 60 / 10 = 6 hours

3. An EV travels 240 km using 40 kWh energy. Find efficiency in km/kWh.

Answer:
Efficiency = Distance / Energy = 240 / 40 = 6 km/kWh

4. Motor input power is 25 kW and output power is 22 kW. Find efficiency.

Answer:
Efficiency = (22 / 25) × 100 = 88%

5. Battery SOC drops from 95% to 35%. Find percentage charge used.

Answer:
Charge used = 95 − 35 = 60%

6. Vehicle uses 48 kWh battery for 300 km. Find Wh/km.

Answer:
Wh/km = 48000 / 300 = 160 Wh/km

7. Battery pack has 96 cells in series, each cell voltage = 3.7 V. Find pack voltage.

Answer:
Pack Voltage = 96 × 3.7 = 355.2 V

8. A motor produces torque of 180 N·m at radius 0.3 m wheel. Find tractive force.

Answer:
Force = Torque / Radius = 180 / 0.3 = 600 N

9. EV runs 180 km with 30 kWh battery. Find energy consumption per km.

Answer:
Consumption = 30000 / 180 = 166.67 Wh/km

10. Battery has 72 Ah capacity. If discharge current is 18 A, estimate discharge time.

Answer:
Time = Ah / A = 72 / 18 = 4 hours

11. Charger supplies 32 A at 240 V. Find charging power in kW.

Answer:
Power = V × I = 240 × 32 = 7680 W = 7.68 kW

12. If electricity cost is ₹8 per kWh, find cost to fully charge 40 kWh battery.

Answer:
Cost = 40 × 8 = ₹320

13. EV travels 250 km on ₹320 charging cost. Find running cost per km.

Answer:
Cost/km = 320 / 250 = ₹1.28/km

14. Battery SOH decreases from 100% to 82%. Find percentage degradation.

Answer:
Degradation = 100 − 82 = 18%

15. A 20 kW motor runs for 2.5 hours. Find energy consumed.

Answer:
Energy = Power × Time = 20 × 2.5 = 50 kWh

16. A battery pack has 120 cells in series, each cell voltage is 3.6 V. Find total pack voltage.

Answer:
Pack Voltage = 120 × 3.6 = 432 V

17. An EV battery is rated 48 kWh. If charger power is 12 kW, find charging time.

Answer:
Time = Energy / Power = 48 / 12 = 4 hours

18. EV covers 360 km using 60 kWh energy. Find efficiency in km/kWh.

Answer:
Efficiency = 360 / 60 = 6 km/kWh

19. Motor input power is 30 kW and output power is 27 kW. Find motor efficiency.

Answer:
Efficiency = (27 / 30) × 100 = 90%

20. Battery SOC falls from 88% to 28%. Find charge used.

Answer:
Charge Used = 88 − 28 = 60%

21. A 54 kWh battery gives range of 270 km. Find Wh/km.

Answer:
Wh/km = 54000 / 270 = 200 Wh/km

22. If discharge current is 20 A from 100 Ah battery, estimate discharge time.

Answer:
Time = 100 / 20 = 5 hours

23. Charger current is 16 A and supply voltage is 230 V. Find charging power.

Answer:
Power = 230 × 16 = 3680 W = 3.68 kW

24. Electricity tariff is ₹9/kWh. Find charging cost for 50 kWh battery.

Answer:
Cost = 50 × 9 = ₹450

25. EV runs 300 km at total charging cost ₹450. Find cost per km.

Answer:
Cost/km = 450 / 300 = ₹1.50/km

26. Battery SOH reduces from 100% to 76%. Find degradation percentage.

Answer:
Degradation = 100 − 76 = 24%

27. A 15 kW motor operates for 3 hours. Find energy consumed.

Answer:
Energy = 15 × 3 = 45 kWh

28. Wheel radius is 0.25 m and motor torque is 125 N·m. Find tractive force.

Answer:
Force = 125 / 0.25 = 500 N

29. EV consumes 36 kWh for 180 km. Find km/kWh.

Answer:
Efficiency = 180 / 36 = 5 km/kWh

30. Battery has 90 Ah capacity. If load current is 30 A, find discharge time.

Answer:
Time = 90 / 30 = 3 hours