The force of gravity depends on mass hence acceleration becomes independent of it. It means two bodies dropped from a height will have same acceleration irrespective their masses. 2. read more
Among the three if F is constant, i.e. fixed then a is inversely proportional to mass. If a is constant then F is directly proportional to mass. If m is constant then F is directly proportional to acceleration. In the case of free fall, a is constant and hence F is directly proportional to mass. read more
ma = G Mm/r^2 This is where we prove acceleration due to gravity is independent of the mass of the falling object - we can cancel it out by dividing through by m a = GM/r^2 Thus acceleration due to gravity is ONLY due to Newton's gravitational constant, the mass of the planet and the distance of the object from the centre of the planet. read more
In an inertial reference frame, the light cones stand upright as light moves away from its source at the same speed in all directions. But in an accelerated frame of reference, the light cone tips in the direction of the acceleration; and the faster the acceleration, the more the light cone tips. read more
Acceleration and mass are two independent physical entities. Acceleration is the rate at which the velocity of a body changes, and mass the measure of matter inside the body. These two quantities are connected in an equation- the Newton's second law of motion- where we define force as product of mass and acceleration. read more