Quizzes
Quiz 1 dated 10 Jan 2023
(Odd roll number)
Quiz 1 dated 10 Jan 2023
(Even roll number)
Quiz 2
Dated 18 Jan 2023
Quiz 2 (A & B are last two digits of your ID resp.)
A Tata Nexon BEV with a (24+(A+B)/10) kWh battery pack has upstream
emissions of 68 gCO2/km in Chennai, 162 gCO2/km in Delhi, and 140 gCO2/km
as an average in India.
• The same Tata Nexon with petrol engine has total emissions of 221 gCO2/km.
• A. How many kilometers must the BEV be driven to result in lower carbon
emissions than the Petrol car in (a) Chennai (b) Delhi and (c) India, if the
cradle-to-grave emissions of CO2 for the electric car and gasoline car are 10,300
kg and 7,500 kg respectively.
• B. Norway has electricity emissions of about 50 times less than India, or about
2.5 gCO2/km. What are the combined cradle-grave and upstream emissions if
the BEV is driven in Norway for 20000 km per year over eight years?
Quiz 3
Dated 25 Jan 2023
Q1
•
Quiz 4
Q 4: Q 1
• An electric vehicle has the following attributes: mass m = 500 kg,
wheel radius r = 0.3 m, gear ratio from rotor to drive axle is 10, and a
nominal gear efficiency is 95%.
• The vehicle is required to accelerate linearly from 0 to {36+(A+B)/5}
km/h in 5 s on a flat road surface under calm wind conditions.
• Neglecting load forces, instantaneously at 18 km/h calculate the
electromagnetic torque from the electric motor to achieve this
acceleration.
Quiz 4: Q2
• The same vehicle is required to decelerate linearly from 36 to 0 km/h
in 5 s on a flat road surface under calm wind conditions. Neglecting
load forces, instantaneously at 18 km/h calculate the regenerative
torque to the electric motor to achieve this braking.
• Quiz 5 dated Feb 8, 2023
Q5: Question 1
• For a new car being developed, a Li-ion battery is proposed with 194
cells of C/3 cell capacity of (50+A+B) Ah at 3.8 V.
• Size of the cell(cubicle) is :
• Length: (60+A) cm Width : (20+B) cm Height: 0.7 cm
• Weight: (800+A+B) gms.
• Find energy in cell when fully charged in wH.
• Calculate Energy density in Wh/liter and Specific energy wh/kg of the
cell.
• Will the specific energy of the Battery Pack be lower or higher than
cell specific energy.
Reference data
• Quiz 6 dated Feb 15, 2023
Q1.
•
Assignment 1 in lieu of Quiz 7
Sizing Fuel Cell System for Heavy Good Tractor–Trailer Combination
•
Quiz 8 Dated March 15, 2023
Questions
• 1. To optimize the fuel consumption of a Hybrid electric vehicle, what
should be the range of RPM for the engine most of the time.
• 2. To optimize the fuel consumption of a Hybrid electric vehicle, what
should be the range of RPM for the motor most of the time.
• (Refer to the charts given for an answer on next page).
• 3. What are the two important control strategies for hybrid electric
vehicles and what is the difference between the two.
Electric motor efficiency charts
IC engine efficiency chart
Quiz 9 March 22, 2023
Questions
• 1. Electric motors are used in industrial applications as well as Electric
Vehicle. Why are the performance requirements of motors in electric
vehicles different from those in industrial application?
• 2. Why did DC motors need commutator for operation? What
innovation led to the development of commutator-less DC motors?
• 3. Why are Permanent magnet AC motors more efficient that AC
Induction motors?
Quiz 10 dated 29 march 2023
Question 1
An electric car has following attributes:
Mass= (2000+10A) kg Length(wheel to wheel) L= (4+.1B)
meters
Center of gravity above ground= 0. 65 meters
Distance of CG from Front wheel La = 0.45 L
It is travelling on plain road at 100 kmph. On spotting an old
man ,just a few meters away, the driver applies sudden brake
causing intending to decelerate the vehicle at 8 m/sq. sec.
A. Find out the Force applied to front wheels and rear wheels if
the vehicle is designed to follow the ideal brake force
distribution curve.
B. If the adhesion coefficient between road and tires is 0.3 ,
then will the wheels jam causing the vehicle to skid. Find out
, which wheels will jam first.
