The drawing shows an extreme skier at three locations on a ski run: (A) a straight section, (B) a circular section, and (C) an airborne phase in which the skier is in free-fall. At the right of the drawing are four possible directions for the net force that acts on the skier. What is the direction of the net force at A, B, and C? Assume that there is no friction or air resistance at any point along the ski run.

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.