Physics question about the equation F=ma?

Question

An object has mass m and it is subjected to a force F. The resulting acceleration of the object is a. Is the relation F=ma valid for all situations? I'm completely stumped at how to answer this in about 3 sentences lol, any help?

Answer 1

i may not give a definate answer but i think that the physics a learnt a year ago could come into play. the equation f=ma suggests that as long as a force is constantly applied to an object, it accelerates assuming its mass is constant. however in real life eg cars have a speed limit where there is no more acceleration, forces like drag affect the resultant force produced and so the acceleration of the car begins to decrease. in conclusion, f=ma is true if there is only one force acting on an object with no other forces acting on the object. also to note is that "f" is the resultant force.

Answer 2

Mass by acceleration is equal to force. Although it seems like it should be velocity instead of acceleration, since not all moving objects are necessarily accelerating.



Say mass is 2 kg, and acceleration is 2 m/s^2 (2 meters per second, per second).



2*2^2=8.



Though, what unit the product is expressed in, I don't know.

Answer 3

F = ma

If an unbalanced force F acts on an object of constant mass m, it produces a constant acceleration a. A situation where it would not apply would be a rocket which is consuming fuel (and losing mass) as it takes off.

A more general form of the equation is

F = dp/dt [=rate of change of momentum]

Answer 4

F=ma is not valid in all situations. As others have noted, if the mass changes, then F=ma doesn't work. F=ma also doesn't work in Relativity and Quantum Mechanics.