Question

Physics question, please help?

Which of these should a free body diagram of a car being driven along a highway include?

A) The horizontal component of force that the tire exerts on the road to accelerate
B) The force of the engine in turning the driveshaft of the car
C) The velocity vector for the moving car
D) The force of gravity on the car

Answer 1

D) The force of gravity on the car

Step-by-step explanation:

The free-body diagram includes all forces applied to the analysed object. Option D is the only one which includes a force (the force of gravity) applied on the car (our analysed object). In Option A, the force is applied on the road, not the car. In option B, similarly, than before, the force is not applied to the car itself. In option C, there is no force involved.

Answer 2

we need to include all the force that act on the car

B) The force of the engine in turning the driveshaft of the car

since this is the force the engine apply on the car to move forward.

D) The force of gravity on the car

since this is the force applied by earth on the car .

since velocity is not a force , we dont include it in the free body diagram.

we dont consider option A also because it mentions force the tire exert on the road while we have to consider the forces acting on the car for the free body diagram of the car.