Question

while driving a car, you take your foot off of the gas pedal and the car begins to coast. ignoring air resistance, which of the following is the correct free - body diagram while the car is coasting? clear all 1 2 3 4

Explanation:

Step1: Analyze forces when car is coasting

When the car is coasting after taking foot - off the gas pedal, there is no driving force ($F_{drive}$). The main forces acting on the car are air resistance ($F_{air}$) and friction ($F_{fric}$) which act in the opposite direction of the car's motion, and the normal force ($F_{norm}$) acting perpendicular to the surface and the gravitational force ($F_{grav}$) acting downwards.

Step2: Evaluate each free - body diagram

Diagram 1 only shows horizontal forces (air resistance), missing vertical forces. Diagram 2 shows both vertical (normal and gravitational) and horizontal (air resistance and friction) forces correctly. Diagram 3 has incorrect orientation of forces and missing some key forces.

Answer:

2