Question

What will happen if the traction force is negative?

(a) The vehicle will accelerate

(b) The vehicle will decelerate

(c) The vehicle will first accelerate and then decelerate

(d) The vehicle will run at a constant speed

This question was posed to me in an online quiz.

This interesting question is from Vehicles and Powertrain in portion Emission Control Methods, Electric & Conventional Vehicles of Automobile Engineering

Answer 1

The correct choice is (b) The vehicle will decelerate

To elaborate: Fnet = mvehicle* avehicle = Ftraction – Frolling – Faerodynamic. If the Ftractionis negative, then Fnet will be more negative ⇒ avehicle is negative. Therefore the vehicle will decelerate.