Question

What will happen if the vehicle is made 50% heavier, but all other parameters remain the same?

(a) The running resistance will decrease

(b) The running resistance will increase

(c) The running resistance will remain the same

(d) The aerodynamic resistance will increase by a factor of 1.5 squared

This question was addressed to me in homework.

I would like to ask this question from Vehicles and Powertrain in section Emission Control Methods, Electric & Conventional Vehicles of Automobile Engineering

Answer 1

Right option is (b) The running resistance will increase

Explanation: Frunning = Frolling + Faerodynamic = (μk * mvehicle * g) + (0.5 * ρ * Cdrag * Afront * V^2). The running resistance is the sum of rolling and aerodynamic resistance. Running resistance is directly proportional to the mass of the vehicle. As the mass of vehicle increases rolling resistance increases and thus, the running resistance increases. The aerodynamic resistance is independent of the vehicle mass.