At high altitudes, pilots and mountain climbers must breathe an enriched mixture containing more oxygen than the standard 21.0% found in ordinary air at sea level. at an altitude of 10500 m, atmospheric pressure is 0.237 atm. what oxygen concentration is required at this altitude if, with each breath, the same number of oxygen molecules is to enter the lungs as for ordinary air at sea level?

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.